Show polynomial division steps

This page demonstrates how to generate ECC blocks by performing polynomial divison on a message polynomial. Just enter the coefficients of the message polynomial and the desired number of ECC blocks, then click Perform Division.

If the steps are unclear, please read the error correction generation section of the tutorial, which includes a detailed explanation of these steps.


(example: 32,91,11,120,209,114,220,77,67,64,236,17,236 )

(example: 13 )

Polynomial Division Steps

The first step to the division is to prepare the message polynomial for the division. The full message polynomial is:

246x14 + 246x13 + 66x12 + 7x11 + 118x10 + 134x9 + 242x8 + 7x7 + 38x6 + 86x5 + 22x4 + 198x3 + 199x2 + 146x1 + 6

To make sure that the exponent of the lead term doesn't become too small during the division, multiply the message polynomial by xn where n is the number of error correction codewords that are needed. In this case n is 18, for 18 error correction codewords, so multiply the message polynomial by x18, which gives us:

246x32 + 246x31 + 66x30 + 7x29 + 118x28 + 134x27 + 242x26 + 7x25 + 38x24 + 86x23 + 22x22 + 198x21 + 199x20 + 146x19 + 6x18

The lead term of the generator polynomial should also have the same exponent, so multiply by x14 to get

α0x32 + α215x31 + α234x30 + α158x29 + α94x28 + α184x27 + α97x26 + α118x25 + α170x24 + α79x23 + α187x22 + α152x21 + α148x20 + α252x19 + α179x18 + α5x17 + α98x16 + α96x15 + α153x14

Now it is possible to perform the repeated division steps. The number of steps in the division must equal the number of terms in the message polynomial. In this case, the division will take 15 steps to complete. This will result in a remainder that has 18 terms. These terms will be the 18 error correction codewords that are required.

Step 1a: Multiply the Generator Polynomial by the Lead Term of the Message Polynomial

The first step is to multiply the generator polynomial by the lead term of the message polynomial. The lead term in this case is 246x32. Since alpha notation makes it easier to perform the multiplication, it is recommended to convert 246x32 to alpha notation. According to the log antilog table, for the integer value 246, the alpha exponent is 173. Therefore 246 = α173. Multiply the generator polynomial by α173:

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α173x32 + α(388 % 255)x31 + α(407 % 255)x30 + α(331 % 255)x29 + α(267 % 255)x28 + α(357 % 255)x27 + α(270 % 255)x26 + α(291 % 255)x25 + α(343 % 255)x24 + α252x23 + α(360 % 255)x22 + α(325 % 255)x21 + α(321 % 255)x20 + α(425 % 255)x19 + α(352 % 255)x18 + α178x17 + α(271 % 255)x16 + α(269 % 255)x15 + α(326 % 255)x14

The result is:

α173x32 + α133x31 + α152x30 + α76x29 + α12x28 + α102x27 + α15x26 + α36x25 + α88x24 + α252x23 + α105x22 + α70x21 + α66x20 + α170x19 + α97x18 + α178x17 + α16x16 + α14x15 + α71x14

Now, convert this to integer notation:

246x32 + 109x31 + 73x30 + 30x29 + 205x28 + 68x27 + 38x26 + 37x25 + 254x24 + 173x23 + 26x22 + 94x21 + 97x20 + 215x19 + 175x18 + 171x17 + 76x16 + 19x15 + 188x14

Step 1b: XOR the result with the message polynomial

Since this is the first division step, XOR the result from 1a with the message polynomial.

(246 ⊕ 246)x32 + (246 ⊕ 109)x31 + (66 ⊕ 73)x30 + (7 ⊕ 30)x29 + (118 ⊕ 205)x28 + (134 ⊕ 68)x27 + (242 ⊕ 38)x26 + (7 ⊕ 37)x25 + (38 ⊕ 254)x24 + (86 ⊕ 173)x23 + (22 ⊕ 26)x22 + (198 ⊕ 94)x21 + (199 ⊕ 97)x20 + (146 ⊕ 215)x19 + (6 ⊕ 175)x18 + (0 ⊕ 171)x17 + (0 ⊕ 76)x16 + (0 ⊕ 19)x15 + (0 ⊕ 188)x14

The result is:

0x32 + 155x31 + 11x30 + 25x29 + 187x28 + 194x27 + 212x26 + 34x25 + 216x24 + 251x23 + 12x22 + 152x21 + 166x20 + 69x19 + 169x18 + 171x17 + 76x16 + 19x15 + 188x14

Discard the lead 0 term to get:

155x31 + 11x30 + 25x29 + 187x28 + 194x27 + 212x26 + 34x25 + 216x24 + 251x23 + 12x22 + 152x21 + 166x20 + 69x19 + 169x18 + 171x17 + 76x16 + 19x15 + 188x14

Step 2a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 155x31. Convert 155x31 to alpha notation. According to the log antilog table, for the integer value 155, the alpha exponent is 217. Therefore 155 = α217. Multiply the generator polynomial by α217:

217 * α0)x31 + (α217 * α215)x30 + (α217 * α234)x29 + (α217 * α158)x28 + (α217 * α94)x27 + (α217 * α184)x26 + (α217 * α97)x25 + (α217 * α118)x24 + (α217 * α170)x23 + (α217 * α79)x22 + (α217 * α187)x21 + (α217 * α152)x20 + (α217 * α148)x19 + (α217 * α252)x18 + (α217 * α179)x17 + (α217 * α5)x16 + (α217 * α98)x15 + (α217 * α96)x14 + (α217 * α153)x13

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α217x31 + α(432 % 255)x30 + α(451 % 255)x29 + α(375 % 255)x28 + α(311 % 255)x27 + α(401 % 255)x26 + α(314 % 255)x25 + α(335 % 255)x24 + α(387 % 255)x23 + α(296 % 255)x22 + α(404 % 255)x21 + α(369 % 255)x20 + α(365 % 255)x19 + α(469 % 255)x18 + α(396 % 255)x17 + α222x16 + α(315 % 255)x15 + α(313 % 255)x14 + α(370 % 255)x13

The result is:

α217x31 + α177x30 + α196x29 + α120x28 + α56x27 + α146x26 + α59x25 + α80x24 + α132x23 + α41x22 + α149x21 + α114x20 + α110x19 + α214x18 + α141x17 + α222x16 + α60x15 + α58x14 + α115x13

Now, convert this to integer notation:

155x31 + 219x30 + 200x29 + 59x28 + 93x27 + 154x26 + 210x25 + 253x24 + 184x23 + 212x22 + 164x21 + 62x20 + 103x19 + 249x18 + 21x17 + 138x16 + 185x15 + 105x14 + 124x13

Step 2b: XOR the result with the result from step 1b

Use the result from step 1b to perform the next XOR.

(155 ⊕ 155)x31 + (11 ⊕ 219)x30 + (25 ⊕ 200)x29 + (187 ⊕ 59)x28 + (194 ⊕ 93)x27 + (212 ⊕ 154)x26 + (34 ⊕ 210)x25 + (216 ⊕ 253)x24 + (251 ⊕ 184)x23 + (12 ⊕ 212)x22 + (152 ⊕ 164)x21 + (166 ⊕ 62)x20 + (69 ⊕ 103)x19 + (169 ⊕ 249)x18 + (171 ⊕ 21)x17 + (76 ⊕ 138)x16 + (19 ⊕ 185)x15 + (188 ⊕ 105)x14 + (0 ⊕ 124)x13

The result is:

0x31 + 208x30 + 209x29 + 128x28 + 159x27 + 78x26 + 240x25 + 37x24 + 67x23 + 216x22 + 60x21 + 152x20 + 34x19 + 80x18 + 190x17 + 198x16 + 170x15 + 213x14 + 124x13

Discard the lead 0 term to get:

208x30 + 209x29 + 128x28 + 159x27 + 78x26 + 240x25 + 37x24 + 67x23 + 216x22 + 60x21 + 152x20 + 34x19 + 80x18 + 190x17 + 198x16 + 170x15 + 213x14 + 124x13

Step 3a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 208x30. Convert 208x30 to alpha notation. According to the log antilog table, for the integer value 208, the alpha exponent is 108. Therefore 208 = α108. Multiply the generator polynomial by α108:

108 * α0)x30 + (α108 * α215)x29 + (α108 * α234)x28 + (α108 * α158)x27 + (α108 * α94)x26 + (α108 * α184)x25 + (α108 * α97)x24 + (α108 * α118)x23 + (α108 * α170)x22 + (α108 * α79)x21 + (α108 * α187)x20 + (α108 * α152)x19 + (α108 * α148)x18 + (α108 * α252)x17 + (α108 * α179)x16 + (α108 * α5)x15 + (α108 * α98)x14 + (α108 * α96)x13 + (α108 * α153)x12

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α108x30 + α(323 % 255)x29 + α(342 % 255)x28 + α(266 % 255)x27 + α202x26 + α(292 % 255)x25 + α205x24 + α226x23 + α(278 % 255)x22 + α187x21 + α(295 % 255)x20 + α(260 % 255)x19 + α(256 % 255)x18 + α(360 % 255)x17 + α(287 % 255)x16 + α113x15 + α206x14 + α204x13 + α(261 % 255)x12

The result is:

α108x30 + α68x29 + α87x28 + α11x27 + α202x26 + α37x25 + α205x24 + α226x23 + α23x22 + α187x21 + α40x20 + α5x19 + α1x18 + α105x17 + α32x16 + α113x15 + α206x14 + α204x13 + α6x12

Now, convert this to integer notation:

208x30 + 153x29 + 127x28 + 232x27 + 112x26 + 74x25 + 167x24 + 72x23 + 201x22 + 220x21 + 106x20 + 32x19 + 2x18 + 26x17 + 157x16 + 31x15 + 83x14 + 221x13 + 64x12

Step 3b: XOR the result with the result from step 2b

Use the result from step 2b to perform the next XOR.

(208 ⊕ 208)x30 + (209 ⊕ 153)x29 + (128 ⊕ 127)x28 + (159 ⊕ 232)x27 + (78 ⊕ 112)x26 + (240 ⊕ 74)x25 + (37 ⊕ 167)x24 + (67 ⊕ 72)x23 + (216 ⊕ 201)x22 + (60 ⊕ 220)x21 + (152 ⊕ 106)x20 + (34 ⊕ 32)x19 + (80 ⊕ 2)x18 + (190 ⊕ 26)x17 + (198 ⊕ 157)x16 + (170 ⊕ 31)x15 + (213 ⊕ 83)x14 + (124 ⊕ 221)x13 + (0 ⊕ 64)x12

The result is:

0x30 + 72x29 + 255x28 + 119x27 + 62x26 + 186x25 + 130x24 + 11x23 + 17x22 + 224x21 + 242x20 + 2x19 + 82x18 + 164x17 + 91x16 + 181x15 + 134x14 + 161x13 + 64x12

Discard the lead 0 term to get:

72x29 + 255x28 + 119x27 + 62x26 + 186x25 + 130x24 + 11x23 + 17x22 + 224x21 + 242x20 + 2x19 + 82x18 + 164x17 + 91x16 + 181x15 + 134x14 + 161x13 + 64x12

Step 4a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 72x29. Convert 72x29 to alpha notation. According to the log antilog table, for the integer value 72, the alpha exponent is 226. Therefore 72 = α226. Multiply the generator polynomial by α226:

226 * α0)x29 + (α226 * α215)x28 + (α226 * α234)x27 + (α226 * α158)x26 + (α226 * α94)x25 + (α226 * α184)x24 + (α226 * α97)x23 + (α226 * α118)x22 + (α226 * α170)x21 + (α226 * α79)x20 + (α226 * α187)x19 + (α226 * α152)x18 + (α226 * α148)x17 + (α226 * α252)x16 + (α226 * α179)x15 + (α226 * α5)x14 + (α226 * α98)x13 + (α226 * α96)x12 + (α226 * α153)x11

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α226x29 + α(441 % 255)x28 + α(460 % 255)x27 + α(384 % 255)x26 + α(320 % 255)x25 + α(410 % 255)x24 + α(323 % 255)x23 + α(344 % 255)x22 + α(396 % 255)x21 + α(305 % 255)x20 + α(413 % 255)x19 + α(378 % 255)x18 + α(374 % 255)x17 + α(478 % 255)x16 + α(405 % 255)x15 + α231x14 + α(324 % 255)x13 + α(322 % 255)x12 + α(379 % 255)x11

The result is:

α226x29 + α186x28 + α205x27 + α129x26 + α65x25 + α155x24 + α68x23 + α89x22 + α141x21 + α50x20 + α158x19 + α123x18 + α119x17 + α223x16 + α150x15 + α231x14 + α69x13 + α67x12 + α124x11

Now, convert this to integer notation:

72x29 + 110x28 + 167x27 + 23x26 + 190x25 + 114x24 + 153x23 + 225x22 + 21x21 + 5x20 + 183x19 + 197x18 + 147x17 + 9x16 + 85x15 + 245x14 + 47x13 + 194x12 + 151x11

Step 4b: XOR the result with the result from step 3b

Use the result from step 3b to perform the next XOR.

(72 ⊕ 72)x29 + (255 ⊕ 110)x28 + (119 ⊕ 167)x27 + (62 ⊕ 23)x26 + (186 ⊕ 190)x25 + (130 ⊕ 114)x24 + (11 ⊕ 153)x23 + (17 ⊕ 225)x22 + (224 ⊕ 21)x21 + (242 ⊕ 5)x20 + (2 ⊕ 183)x19 + (82 ⊕ 197)x18 + (164 ⊕ 147)x17 + (91 ⊕ 9)x16 + (181 ⊕ 85)x15 + (134 ⊕ 245)x14 + (161 ⊕ 47)x13 + (64 ⊕ 194)x12 + (0 ⊕ 151)x11

The result is:

0x29 + 145x28 + 208x27 + 41x26 + 4x25 + 240x24 + 146x23 + 240x22 + 245x21 + 247x20 + 181x19 + 151x18 + 55x17 + 82x16 + 224x15 + 115x14 + 142x13 + 130x12 + 151x11

Discard the lead 0 term to get:

145x28 + 208x27 + 41x26 + 4x25 + 240x24 + 146x23 + 240x22 + 245x21 + 247x20 + 181x19 + 151x18 + 55x17 + 82x16 + 224x15 + 115x14 + 142x13 + 130x12 + 151x11

Step 5a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 145x28. Convert 145x28 to alpha notation. According to the log antilog table, for the integer value 145, the alpha exponent is 165. Therefore 145 = α165. Multiply the generator polynomial by α165:

165 * α0)x28 + (α165 * α215)x27 + (α165 * α234)x26 + (α165 * α158)x25 + (α165 * α94)x24 + (α165 * α184)x23 + (α165 * α97)x22 + (α165 * α118)x21 + (α165 * α170)x20 + (α165 * α79)x19 + (α165 * α187)x18 + (α165 * α152)x17 + (α165 * α148)x16 + (α165 * α252)x15 + (α165 * α179)x14 + (α165 * α5)x13 + (α165 * α98)x12 + (α165 * α96)x11 + (α165 * α153)x10

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α165x28 + α(380 % 255)x27 + α(399 % 255)x26 + α(323 % 255)x25 + α(259 % 255)x24 + α(349 % 255)x23 + α(262 % 255)x22 + α(283 % 255)x21 + α(335 % 255)x20 + α244x19 + α(352 % 255)x18 + α(317 % 255)x17 + α(313 % 255)x16 + α(417 % 255)x15 + α(344 % 255)x14 + α170x13 + α(263 % 255)x12 + α(261 % 255)x11 + α(318 % 255)x10

The result is:

α165x28 + α125x27 + α144x26 + α68x25 + α4x24 + α94x23 + α7x22 + α28x21 + α80x20 + α244x19 + α97x18 + α62x17 + α58x16 + α162x15 + α89x14 + α170x13 + α8x12 + α6x11 + α63x10

Now, convert this to integer notation:

145x28 + 51x27 + 168x26 + 153x25 + 16x24 + 113x23 + 128x22 + 24x21 + 253x20 + 250x19 + 175x18 + 222x17 + 105x16 + 191x15 + 225x14 + 215x13 + 29x12 + 64x11 + 161x10

Step 5b: XOR the result with the result from step 4b

Use the result from step 4b to perform the next XOR.

(145 ⊕ 145)x28 + (208 ⊕ 51)x27 + (41 ⊕ 168)x26 + (4 ⊕ 153)x25 + (240 ⊕ 16)x24 + (146 ⊕ 113)x23 + (240 ⊕ 128)x22 + (245 ⊕ 24)x21 + (247 ⊕ 253)x20 + (181 ⊕ 250)x19 + (151 ⊕ 175)x18 + (55 ⊕ 222)x17 + (82 ⊕ 105)x16 + (224 ⊕ 191)x15 + (115 ⊕ 225)x14 + (142 ⊕ 215)x13 + (130 ⊕ 29)x12 + (151 ⊕ 64)x11 + (0 ⊕ 161)x10

The result is:

0x28 + 227x27 + 129x26 + 157x25 + 224x24 + 227x23 + 112x22 + 237x21 + 10x20 + 79x19 + 56x18 + 233x17 + 59x16 + 95x15 + 146x14 + 89x13 + 159x12 + 215x11 + 161x10

Discard the lead 0 term to get:

227x27 + 129x26 + 157x25 + 224x24 + 227x23 + 112x22 + 237x21 + 10x20 + 79x19 + 56x18 + 233x17 + 59x16 + 95x15 + 146x14 + 89x13 + 159x12 + 215x11 + 161x10

Step 6a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 227x27. Convert 227x27 to alpha notation. According to the log antilog table, for the integer value 227, the alpha exponent is 176. Therefore 227 = α176. Multiply the generator polynomial by α176:

176 * α0)x27 + (α176 * α215)x26 + (α176 * α234)x25 + (α176 * α158)x24 + (α176 * α94)x23 + (α176 * α184)x22 + (α176 * α97)x21 + (α176 * α118)x20 + (α176 * α170)x19 + (α176 * α79)x18 + (α176 * α187)x17 + (α176 * α152)x16 + (α176 * α148)x15 + (α176 * α252)x14 + (α176 * α179)x13 + (α176 * α5)x12 + (α176 * α98)x11 + (α176 * α96)x10 + (α176 * α153)x9

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α176x27 + α(391 % 255)x26 + α(410 % 255)x25 + α(334 % 255)x24 + α(270 % 255)x23 + α(360 % 255)x22 + α(273 % 255)x21 + α(294 % 255)x20 + α(346 % 255)x19 + α255x18 + α(363 % 255)x17 + α(328 % 255)x16 + α(324 % 255)x15 + α(428 % 255)x14 + α(355 % 255)x13 + α181x12 + α(274 % 255)x11 + α(272 % 255)x10 + α(329 % 255)x9

The result is:

α176x27 + α136x26 + α155x25 + α79x24 + α15x23 + α105x22 + α18x21 + α39x20 + α91x19 + α0x18 + α108x17 + α73x16 + α69x15 + α173x14 + α100x13 + α181x12 + α19x11 + α17x10 + α74x9

Now, convert this to integer notation:

227x27 + 79x26 + 114x25 + 240x24 + 38x23 + 26x22 + 45x21 + 53x20 + 163x19 + 1x18 + 208x17 + 202x16 + 47x15 + 246x14 + 17x13 + 49x12 + 90x11 + 152x10 + 137x9

Step 6b: XOR the result with the result from step 5b

Use the result from step 5b to perform the next XOR.

(227 ⊕ 227)x27 + (129 ⊕ 79)x26 + (157 ⊕ 114)x25 + (224 ⊕ 240)x24 + (227 ⊕ 38)x23 + (112 ⊕ 26)x22 + (237 ⊕ 45)x21 + (10 ⊕ 53)x20 + (79 ⊕ 163)x19 + (56 ⊕ 1)x18 + (233 ⊕ 208)x17 + (59 ⊕ 202)x16 + (95 ⊕ 47)x15 + (146 ⊕ 246)x14 + (89 ⊕ 17)x13 + (159 ⊕ 49)x12 + (215 ⊕ 90)x11 + (161 ⊕ 152)x10 + (0 ⊕ 137)x9

The result is:

0x27 + 206x26 + 239x25 + 16x24 + 197x23 + 106x22 + 192x21 + 63x20 + 236x19 + 57x18 + 57x17 + 241x16 + 112x15 + 100x14 + 72x13 + 174x12 + 141x11 + 57x10 + 137x9

Discard the lead 0 term to get:

206x26 + 239x25 + 16x24 + 197x23 + 106x22 + 192x21 + 63x20 + 236x19 + 57x18 + 57x17 + 241x16 + 112x15 + 100x14 + 72x13 + 174x12 + 141x11 + 57x10 + 137x9

Step 7a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 206x26. Convert 206x26 to alpha notation. According to the log antilog table, for the integer value 206, the alpha exponent is 111. Therefore 206 = α111. Multiply the generator polynomial by α111:

111 * α0)x26 + (α111 * α215)x25 + (α111 * α234)x24 + (α111 * α158)x23 + (α111 * α94)x22 + (α111 * α184)x21 + (α111 * α97)x20 + (α111 * α118)x19 + (α111 * α170)x18 + (α111 * α79)x17 + (α111 * α187)x16 + (α111 * α152)x15 + (α111 * α148)x14 + (α111 * α252)x13 + (α111 * α179)x12 + (α111 * α5)x11 + (α111 * α98)x10 + (α111 * α96)x9 + (α111 * α153)x8

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α111x26 + α(326 % 255)x25 + α(345 % 255)x24 + α(269 % 255)x23 + α205x22 + α(295 % 255)x21 + α208x20 + α229x19 + α(281 % 255)x18 + α190x17 + α(298 % 255)x16 + α(263 % 255)x15 + α(259 % 255)x14 + α(363 % 255)x13 + α(290 % 255)x12 + α116x11 + α209x10 + α207x9 + α(264 % 255)x8

The result is:

α111x26 + α71x25 + α90x24 + α14x23 + α205x22 + α40x21 + α208x20 + α229x19 + α26x18 + α190x17 + α43x16 + α8x15 + α4x14 + α108x13 + α35x12 + α116x11 + α209x10 + α207x9 + α9x8

Now, convert this to integer notation:

206x26 + 188x25 + 223x24 + 19x23 + 167x22 + 106x21 + 81x20 + 122x19 + 6x18 + 174x17 + 119x16 + 29x15 + 16x14 + 208x13 + 156x12 + 248x11 + 162x10 + 166x9 + 58x8

Step 7b: XOR the result with the result from step 6b

Use the result from step 6b to perform the next XOR.

(206 ⊕ 206)x26 + (239 ⊕ 188)x25 + (16 ⊕ 223)x24 + (197 ⊕ 19)x23 + (106 ⊕ 167)x22 + (192 ⊕ 106)x21 + (63 ⊕ 81)x20 + (236 ⊕ 122)x19 + (57 ⊕ 6)x18 + (57 ⊕ 174)x17 + (241 ⊕ 119)x16 + (112 ⊕ 29)x15 + (100 ⊕ 16)x14 + (72 ⊕ 208)x13 + (174 ⊕ 156)x12 + (141 ⊕ 248)x11 + (57 ⊕ 162)x10 + (137 ⊕ 166)x9 + (0 ⊕ 58)x8

The result is:

0x26 + 83x25 + 207x24 + 214x23 + 205x22 + 170x21 + 110x20 + 150x19 + 63x18 + 151x17 + 134x16 + 109x15 + 116x14 + 152x13 + 50x12 + 117x11 + 155x10 + 47x9 + 58x8

Discard the lead 0 term to get:

83x25 + 207x24 + 214x23 + 205x22 + 170x21 + 110x20 + 150x19 + 63x18 + 151x17 + 134x16 + 109x15 + 116x14 + 152x13 + 50x12 + 117x11 + 155x10 + 47x9 + 58x8

Step 8a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 83x25. Convert 83x25 to alpha notation. According to the log antilog table, for the integer value 83, the alpha exponent is 206. Therefore 83 = α206. Multiply the generator polynomial by α206:

206 * α0)x25 + (α206 * α215)x24 + (α206 * α234)x23 + (α206 * α158)x22 + (α206 * α94)x21 + (α206 * α184)x20 + (α206 * α97)x19 + (α206 * α118)x18 + (α206 * α170)x17 + (α206 * α79)x16 + (α206 * α187)x15 + (α206 * α152)x14 + (α206 * α148)x13 + (α206 * α252)x12 + (α206 * α179)x11 + (α206 * α5)x10 + (α206 * α98)x9 + (α206 * α96)x8 + (α206 * α153)x7

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α206x25 + α(421 % 255)x24 + α(440 % 255)x23 + α(364 % 255)x22 + α(300 % 255)x21 + α(390 % 255)x20 + α(303 % 255)x19 + α(324 % 255)x18 + α(376 % 255)x17 + α(285 % 255)x16 + α(393 % 255)x15 + α(358 % 255)x14 + α(354 % 255)x13 + α(458 % 255)x12 + α(385 % 255)x11 + α211x10 + α(304 % 255)x9 + α(302 % 255)x8 + α(359 % 255)x7

The result is:

α206x25 + α166x24 + α185x23 + α109x22 + α45x21 + α135x20 + α48x19 + α69x18 + α121x17 + α30x16 + α138x15 + α103x14 + α99x13 + α203x12 + α130x11 + α211x10 + α49x9 + α47x8 + α104x7

Now, convert this to integer notation:

83x25 + 63x24 + 55x23 + 189x22 + 193x21 + 169x20 + 70x19 + 47x18 + 118x17 + 96x16 + 33x15 + 136x14 + 134x13 + 224x12 + 46x11 + 178x10 + 140x9 + 35x8 + 13x7

Step 8b: XOR the result with the result from step 7b

Use the result from step 7b to perform the next XOR.

(83 ⊕ 83)x25 + (207 ⊕ 63)x24 + (214 ⊕ 55)x23 + (205 ⊕ 189)x22 + (170 ⊕ 193)x21 + (110 ⊕ 169)x20 + (150 ⊕ 70)x19 + (63 ⊕ 47)x18 + (151 ⊕ 118)x17 + (134 ⊕ 96)x16 + (109 ⊕ 33)x15 + (116 ⊕ 136)x14 + (152 ⊕ 134)x13 + (50 ⊕ 224)x12 + (117 ⊕ 46)x11 + (155 ⊕ 178)x10 + (47 ⊕ 140)x9 + (58 ⊕ 35)x8 + (0 ⊕ 13)x7

The result is:

0x25 + 240x24 + 225x23 + 112x22 + 107x21 + 199x20 + 208x19 + 16x18 + 225x17 + 230x16 + 76x15 + 252x14 + 30x13 + 210x12 + 91x11 + 41x10 + 163x9 + 25x8 + 13x7

Discard the lead 0 term to get:

240x24 + 225x23 + 112x22 + 107x21 + 199x20 + 208x19 + 16x18 + 225x17 + 230x16 + 76x15 + 252x14 + 30x13 + 210x12 + 91x11 + 41x10 + 163x9 + 25x8 + 13x7

Step 9a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 240x24. Convert 240x24 to alpha notation. According to the log antilog table, for the integer value 240, the alpha exponent is 79. Therefore 240 = α79. Multiply the generator polynomial by α79:

79 * α0)x24 + (α79 * α215)x23 + (α79 * α234)x22 + (α79 * α158)x21 + (α79 * α94)x20 + (α79 * α184)x19 + (α79 * α97)x18 + (α79 * α118)x17 + (α79 * α170)x16 + (α79 * α79)x15 + (α79 * α187)x14 + (α79 * α152)x13 + (α79 * α148)x12 + (α79 * α252)x11 + (α79 * α179)x10 + (α79 * α5)x9 + (α79 * α98)x8 + (α79 * α96)x7 + (α79 * α153)x6

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α79x24 + α(294 % 255)x23 + α(313 % 255)x22 + α237x21 + α173x20 + α(263 % 255)x19 + α176x18 + α197x17 + α249x16 + α158x15 + α(266 % 255)x14 + α231x13 + α227x12 + α(331 % 255)x11 + α(258 % 255)x10 + α84x9 + α177x8 + α175x7 + α232x6

The result is:

α79x24 + α39x23 + α58x22 + α237x21 + α173x20 + α8x19 + α176x18 + α197x17 + α249x16 + α158x15 + α11x14 + α231x13 + α227x12 + α76x11 + α3x10 + α84x9 + α177x8 + α175x7 + α232x6

Now, convert this to integer notation:

240x24 + 53x23 + 105x22 + 139x21 + 246x20 + 29x19 + 227x18 + 141x17 + 54x16 + 183x15 + 232x14 + 245x13 + 144x12 + 30x11 + 8x10 + 107x9 + 219x8 + 255x7 + 247x6

Step 9b: XOR the result with the result from step 8b

Use the result from step 8b to perform the next XOR.

(240 ⊕ 240)x24 + (225 ⊕ 53)x23 + (112 ⊕ 105)x22 + (107 ⊕ 139)x21 + (199 ⊕ 246)x20 + (208 ⊕ 29)x19 + (16 ⊕ 227)x18 + (225 ⊕ 141)x17 + (230 ⊕ 54)x16 + (76 ⊕ 183)x15 + (252 ⊕ 232)x14 + (30 ⊕ 245)x13 + (210 ⊕ 144)x12 + (91 ⊕ 30)x11 + (41 ⊕ 8)x10 + (163 ⊕ 107)x9 + (25 ⊕ 219)x8 + (13 ⊕ 255)x7 + (0 ⊕ 247)x6

The result is:

0x24 + 212x23 + 25x22 + 224x21 + 49x20 + 205x19 + 243x18 + 108x17 + 208x16 + 251x15 + 20x14 + 235x13 + 66x12 + 69x11 + 33x10 + 200x9 + 194x8 + 242x7 + 247x6

Discard the lead 0 term to get:

212x23 + 25x22 + 224x21 + 49x20 + 205x19 + 243x18 + 108x17 + 208x16 + 251x15 + 20x14 + 235x13 + 66x12 + 69x11 + 33x10 + 200x9 + 194x8 + 242x7 + 247x6

Step 10a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 212x23. Convert 212x23 to alpha notation. According to the log antilog table, for the integer value 212, the alpha exponent is 41. Therefore 212 = α41. Multiply the generator polynomial by α41:

41 * α0)x23 + (α41 * α215)x22 + (α41 * α234)x21 + (α41 * α158)x20 + (α41 * α94)x19 + (α41 * α184)x18 + (α41 * α97)x17 + (α41 * α118)x16 + (α41 * α170)x15 + (α41 * α79)x14 + (α41 * α187)x13 + (α41 * α152)x12 + (α41 * α148)x11 + (α41 * α252)x10 + (α41 * α179)x9 + (α41 * α5)x8 + (α41 * α98)x7 + (α41 * α96)x6 + (α41 * α153)x5

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α41x23 + α(256 % 255)x22 + α(275 % 255)x21 + α199x20 + α135x19 + α225x18 + α138x17 + α159x16 + α211x15 + α120x14 + α228x13 + α193x12 + α189x11 + α(293 % 255)x10 + α220x9 + α46x8 + α139x7 + α137x6 + α194x5

The result is:

α41x23 + α1x22 + α20x21 + α199x20 + α135x19 + α225x18 + α138x17 + α159x16 + α211x15 + α120x14 + α228x13 + α193x12 + α189x11 + α38x10 + α220x9 + α46x8 + α139x7 + α137x6 + α194x5

Now, convert this to integer notation:

212x23 + 2x22 + 180x21 + 14x20 + 169x19 + 36x18 + 33x17 + 115x16 + 178x15 + 59x14 + 61x13 + 25x12 + 87x11 + 148x10 + 172x9 + 159x8 + 66x7 + 158x6 + 50x5

Step 10b: XOR the result with the result from step 9b

Use the result from step 9b to perform the next XOR.

(212 ⊕ 212)x23 + (25 ⊕ 2)x22 + (224 ⊕ 180)x21 + (49 ⊕ 14)x20 + (205 ⊕ 169)x19 + (243 ⊕ 36)x18 + (108 ⊕ 33)x17 + (208 ⊕ 115)x16 + (251 ⊕ 178)x15 + (20 ⊕ 59)x14 + (235 ⊕ 61)x13 + (66 ⊕ 25)x12 + (69 ⊕ 87)x11 + (33 ⊕ 148)x10 + (200 ⊕ 172)x9 + (194 ⊕ 159)x8 + (242 ⊕ 66)x7 + (247 ⊕ 158)x6 + (0 ⊕ 50)x5

The result is:

0x23 + 27x22 + 84x21 + 63x20 + 100x19 + 215x18 + 77x17 + 163x16 + 73x15 + 47x14 + 214x13 + 91x12 + 18x11 + 181x10 + 100x9 + 93x8 + 176x7 + 105x6 + 50x5

Discard the lead 0 term to get:

27x22 + 84x21 + 63x20 + 100x19 + 215x18 + 77x17 + 163x16 + 73x15 + 47x14 + 214x13 + 91x12 + 18x11 + 181x10 + 100x9 + 93x8 + 176x7 + 105x6 + 50x5

Step 11a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 27x22. Convert 27x22 to alpha notation. According to the log antilog table, for the integer value 27, the alpha exponent is 248. Therefore 27 = α248. Multiply the generator polynomial by α248:

248 * α0)x22 + (α248 * α215)x21 + (α248 * α234)x20 + (α248 * α158)x19 + (α248 * α94)x18 + (α248 * α184)x17 + (α248 * α97)x16 + (α248 * α118)x15 + (α248 * α170)x14 + (α248 * α79)x13 + (α248 * α187)x12 + (α248 * α152)x11 + (α248 * α148)x10 + (α248 * α252)x9 + (α248 * α179)x8 + (α248 * α5)x7 + (α248 * α98)x6 + (α248 * α96)x5 + (α248 * α153)x4

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α248x22 + α(463 % 255)x21 + α(482 % 255)x20 + α(406 % 255)x19 + α(342 % 255)x18 + α(432 % 255)x17 + α(345 % 255)x16 + α(366 % 255)x15 + α(418 % 255)x14 + α(327 % 255)x13 + α(435 % 255)x12 + α(400 % 255)x11 + α(396 % 255)x10 + α(500 % 255)x9 + α(427 % 255)x8 + α253x7 + α(346 % 255)x6 + α(344 % 255)x5 + α(401 % 255)x4

The result is:

α248x22 + α208x21 + α227x20 + α151x19 + α87x18 + α177x17 + α90x16 + α111x15 + α163x14 + α72x13 + α180x12 + α145x11 + α141x10 + α245x9 + α172x8 + α253x7 + α91x6 + α89x5 + α146x4

Now, convert this to integer notation:

27x22 + 81x21 + 144x20 + 170x19 + 127x18 + 219x17 + 223x16 + 206x15 + 99x14 + 101x13 + 150x12 + 77x11 + 21x10 + 233x9 + 123x8 + 71x7 + 163x6 + 225x5 + 154x4

Step 11b: XOR the result with the result from step 10b

Use the result from step 10b to perform the next XOR.

(27 ⊕ 27)x22 + (84 ⊕ 81)x21 + (63 ⊕ 144)x20 + (100 ⊕ 170)x19 + (215 ⊕ 127)x18 + (77 ⊕ 219)x17 + (163 ⊕ 223)x16 + (73 ⊕ 206)x15 + (47 ⊕ 99)x14 + (214 ⊕ 101)x13 + (91 ⊕ 150)x12 + (18 ⊕ 77)x11 + (181 ⊕ 21)x10 + (100 ⊕ 233)x9 + (93 ⊕ 123)x8 + (176 ⊕ 71)x7 + (105 ⊕ 163)x6 + (50 ⊕ 225)x5 + (0 ⊕ 154)x4

The result is:

0x22 + 5x21 + 175x20 + 206x19 + 168x18 + 150x17 + 124x16 + 135x15 + 76x14 + 179x13 + 205x12 + 95x11 + 160x10 + 141x9 + 38x8 + 247x7 + 202x6 + 211x5 + 154x4

Discard the lead 0 term to get:

5x21 + 175x20 + 206x19 + 168x18 + 150x17 + 124x16 + 135x15 + 76x14 + 179x13 + 205x12 + 95x11 + 160x10 + 141x9 + 38x8 + 247x7 + 202x6 + 211x5 + 154x4

Step 12a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 5x21. Convert 5x21 to alpha notation. According to the log antilog table, for the integer value 5, the alpha exponent is 50. Therefore 5 = α50. Multiply the generator polynomial by α50:

50 * α0)x21 + (α50 * α215)x20 + (α50 * α234)x19 + (α50 * α158)x18 + (α50 * α94)x17 + (α50 * α184)x16 + (α50 * α97)x15 + (α50 * α118)x14 + (α50 * α170)x13 + (α50 * α79)x12 + (α50 * α187)x11 + (α50 * α152)x10 + (α50 * α148)x9 + (α50 * α252)x8 + (α50 * α179)x7 + (α50 * α5)x6 + (α50 * α98)x5 + (α50 * α96)x4 + (α50 * α153)x3

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α50x21 + α(265 % 255)x20 + α(284 % 255)x19 + α208x18 + α144x17 + α234x16 + α147x15 + α168x14 + α220x13 + α129x12 + α237x11 + α202x10 + α198x9 + α(302 % 255)x8 + α229x7 + α55x6 + α148x5 + α146x4 + α203x3

The result is:

α50x21 + α10x20 + α29x19 + α208x18 + α144x17 + α234x16 + α147x15 + α168x14 + α220x13 + α129x12 + α237x11 + α202x10 + α198x9 + α47x8 + α229x7 + α55x6 + α148x5 + α146x4 + α203x3

Now, convert this to integer notation:

5x21 + 116x20 + 48x19 + 81x18 + 168x17 + 251x16 + 41x15 + 252x14 + 172x13 + 23x12 + 139x11 + 112x10 + 7x9 + 35x8 + 122x7 + 160x6 + 82x5 + 154x4 + 224x3

Step 12b: XOR the result with the result from step 11b

Use the result from step 11b to perform the next XOR.

(5 ⊕ 5)x21 + (175 ⊕ 116)x20 + (206 ⊕ 48)x19 + (168 ⊕ 81)x18 + (150 ⊕ 168)x17 + (124 ⊕ 251)x16 + (135 ⊕ 41)x15 + (76 ⊕ 252)x14 + (179 ⊕ 172)x13 + (205 ⊕ 23)x12 + (95 ⊕ 139)x11 + (160 ⊕ 112)x10 + (141 ⊕ 7)x9 + (38 ⊕ 35)x8 + (247 ⊕ 122)x7 + (202 ⊕ 160)x6 + (211 ⊕ 82)x5 + (154 ⊕ 154)x4 + (0 ⊕ 224)x3

The result is:

0x21 + 219x20 + 254x19 + 249x18 + 62x17 + 135x16 + 174x15 + 176x14 + 31x13 + 218x12 + 212x11 + 208x10 + 138x9 + 5x8 + 141x7 + 106x6 + 129x5 + 0x4 + 224x3

Discard the lead 0 term to get:

219x20 + 254x19 + 249x18 + 62x17 + 135x16 + 174x15 + 176x14 + 31x13 + 218x12 + 212x11 + 208x10 + 138x9 + 5x8 + 141x7 + 106x6 + 129x5 + 0x4 + 224x3

Step 13a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 219x20. Convert 219x20 to alpha notation. According to the log antilog table, for the integer value 219, the alpha exponent is 177. Therefore 219 = α177. Multiply the generator polynomial by α177:

177 * α0)x20 + (α177 * α215)x19 + (α177 * α234)x18 + (α177 * α158)x17 + (α177 * α94)x16 + (α177 * α184)x15 + (α177 * α97)x14 + (α177 * α118)x13 + (α177 * α170)x12 + (α177 * α79)x11 + (α177 * α187)x10 + (α177 * α152)x9 + (α177 * α148)x8 + (α177 * α252)x7 + (α177 * α179)x6 + (α177 * α5)x5 + (α177 * α98)x4 + (α177 * α96)x3 + (α177 * α153)x2

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α177x20 + α(392 % 255)x19 + α(411 % 255)x18 + α(335 % 255)x17 + α(271 % 255)x16 + α(361 % 255)x15 + α(274 % 255)x14 + α(295 % 255)x13 + α(347 % 255)x12 + α(256 % 255)x11 + α(364 % 255)x10 + α(329 % 255)x9 + α(325 % 255)x8 + α(429 % 255)x7 + α(356 % 255)x6 + α182x5 + α(275 % 255)x4 + α(273 % 255)x3 + α(330 % 255)x2

The result is:

α177x20 + α137x19 + α156x18 + α80x17 + α16x16 + α106x15 + α19x14 + α40x13 + α92x12 + α1x11 + α109x10 + α74x9 + α70x8 + α174x7 + α101x6 + α182x5 + α20x4 + α18x3 + α75x2

Now, convert this to integer notation:

219x20 + 158x19 + 228x18 + 253x17 + 76x16 + 52x15 + 90x14 + 106x13 + 91x12 + 2x11 + 189x10 + 137x9 + 94x8 + 241x7 + 34x6 + 98x5 + 180x4 + 45x3 + 15x2

Step 13b: XOR the result with the result from step 12b

Use the result from step 12b to perform the next XOR.

(219 ⊕ 219)x20 + (254 ⊕ 158)x19 + (249 ⊕ 228)x18 + (62 ⊕ 253)x17 + (135 ⊕ 76)x16 + (174 ⊕ 52)x15 + (176 ⊕ 90)x14 + (31 ⊕ 106)x13 + (218 ⊕ 91)x12 + (212 ⊕ 2)x11 + (208 ⊕ 189)x10 + (138 ⊕ 137)x9 + (5 ⊕ 94)x8 + (141 ⊕ 241)x7 + (106 ⊕ 34)x6 + (129 ⊕ 98)x5 + (0 ⊕ 180)x4 + (224 ⊕ 45)x3 + (0 ⊕ 15)x2

The result is:

0x20 + 96x19 + 29x18 + 195x17 + 203x16 + 154x15 + 234x14 + 117x13 + 129x12 + 214x11 + 109x10 + 3x9 + 91x8 + 124x7 + 72x6 + 227x5 + 180x4 + 205x3 + 15x2

Discard the lead 0 term to get:

96x19 + 29x18 + 195x17 + 203x16 + 154x15 + 234x14 + 117x13 + 129x12 + 214x11 + 109x10 + 3x9 + 91x8 + 124x7 + 72x6 + 227x5 + 180x4 + 205x3 + 15x2

Step 14a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 96x19. Convert 96x19 to alpha notation. According to the log antilog table, for the integer value 96, the alpha exponent is 30. Therefore 96 = α30. Multiply the generator polynomial by α30:

30 * α0)x19 + (α30 * α215)x18 + (α30 * α234)x17 + (α30 * α158)x16 + (α30 * α94)x15 + (α30 * α184)x14 + (α30 * α97)x13 + (α30 * α118)x12 + (α30 * α170)x11 + (α30 * α79)x10 + (α30 * α187)x9 + (α30 * α152)x8 + (α30 * α148)x7 + (α30 * α252)x6 + (α30 * α179)x5 + (α30 * α5)x4 + (α30 * α98)x3 + (α30 * α96)x2 + (α30 * α153)x1

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α30x19 + α245x18 + α(264 % 255)x17 + α188x16 + α124x15 + α214x14 + α127x13 + α148x12 + α200x11 + α109x10 + α217x9 + α182x8 + α178x7 + α(282 % 255)x6 + α209x5 + α35x4 + α128x3 + α126x2 + α183x1

The result is:

α30x19 + α245x18 + α9x17 + α188x16 + α124x15 + α214x14 + α127x13 + α148x12 + α200x11 + α109x10 + α217x9 + α182x8 + α178x7 + α27x6 + α209x5 + α35x4 + α128x3 + α126x2 + α183x1

Now, convert this to integer notation:

96x19 + 233x18 + 58x17 + 165x16 + 151x15 + 249x14 + 204x13 + 82x12 + 28x11 + 189x10 + 155x9 + 98x8 + 171x7 + 12x6 + 162x5 + 156x4 + 133x3 + 102x2 + 196x1

Step 14b: XOR the result with the result from step 13b

Use the result from step 13b to perform the next XOR.

(96 ⊕ 96)x19 + (29 ⊕ 233)x18 + (195 ⊕ 58)x17 + (203 ⊕ 165)x16 + (154 ⊕ 151)x15 + (234 ⊕ 249)x14 + (117 ⊕ 204)x13 + (129 ⊕ 82)x12 + (214 ⊕ 28)x11 + (109 ⊕ 189)x10 + (3 ⊕ 155)x9 + (91 ⊕ 98)x8 + (124 ⊕ 171)x7 + (72 ⊕ 12)x6 + (227 ⊕ 162)x5 + (180 ⊕ 156)x4 + (205 ⊕ 133)x3 + (15 ⊕ 102)x2 + (0 ⊕ 196)x1

The result is:

0x19 + 244x18 + 249x17 + 110x16 + 13x15 + 19x14 + 185x13 + 211x12 + 202x11 + 208x10 + 152x9 + 57x8 + 215x7 + 68x6 + 65x5 + 40x4 + 72x3 + 105x2 + 196x1

Discard the lead 0 term to get:

244x18 + 249x17 + 110x16 + 13x15 + 19x14 + 185x13 + 211x12 + 202x11 + 208x10 + 152x9 + 57x8 + 215x7 + 68x6 + 65x5 + 40x4 + 72x3 + 105x2 + 196x1

Step 15a: Multiply the Generator Polynomial by the Lead Term of the XOR result from the previous step

Next, multiply the generator polynomial by the lead term of the XOR result from the previous step. The lead term in this case is 244x18. Convert 244x18 to alpha notation. According to the log antilog table, for the integer value 244, the alpha exponent is 230. Therefore 244 = α230. Multiply the generator polynomial by α230:

230 * α0)x18 + (α230 * α215)x17 + (α230 * α234)x16 + (α230 * α158)x15 + (α230 * α94)x14 + (α230 * α184)x13 + (α230 * α97)x12 + (α230 * α118)x11 + (α230 * α170)x10 + (α230 * α79)x9 + (α230 * α187)x8 + (α230 * α152)x7 + (α230 * α148)x6 + (α230 * α252)x5 + (α230 * α179)x4 + (α230 * α5)x3 + (α230 * α98)x2 + (α230 * α96)x1 + (α230 * α153)x0

The exponents of the alphas are added together. In this case, at least one of the exponents is larger than 255, so perform modulo 255 as follows:

α230x18 + α(445 % 255)x17 + α(464 % 255)x16 + α(388 % 255)x15 + α(324 % 255)x14 + α(414 % 255)x13 + α(327 % 255)x12 + α(348 % 255)x11 + α(400 % 255)x10 + α(309 % 255)x9 + α(417 % 255)x8 + α(382 % 255)x7 + α(378 % 255)x6 + α(482 % 255)x5 + α(409 % 255)x4 + α235x3 + α(328 % 255)x2 + α(326 % 255)x1 + α(383 % 255)x0

The result is:

α230x18 + α190x17 + α209x16 + α133x15 + α69x14 + α159x13 + α72x12 + α93x11 + α145x10 + α54x9 + α162x8 + α127x7 + α123x6 + α227x5 + α154x4 + α235x3 + α73x2 + α71x1 + α128x0

Now, convert this to integer notation:

244x18 + 174x17 + 162x16 + 109x15 + 47x14 + 115x13 + 101x12 + 182x11 + 77x10 + 80x9 + 191x8 + 204x7 + 197x6 + 144x5 + 57x4 + 235x3 + 202x2 + 188x1 + 133

Step 15b: XOR the result with the result from step 14b

Use the result from step 14b to perform the next XOR.

(244 ⊕ 244)x18 + (249 ⊕ 174)x17 + (110 ⊕ 162)x16 + (13 ⊕ 109)x15 + (19 ⊕ 47)x14 + (185 ⊕ 115)x13 + (211 ⊕ 101)x12 + (202 ⊕ 182)x11 + (208 ⊕ 77)x10 + (152 ⊕ 80)x9 + (57 ⊕ 191)x8 + (215 ⊕ 204)x7 + (68 ⊕ 197)x6 + (65 ⊕ 144)x5 + (40 ⊕ 57)x4 + (72 ⊕ 235)x3 + (105 ⊕ 202)x2 + (196 ⊕ 188)x1 + (0 ⊕ 133)x0

The result is:

0x18 + 87x17 + 204x16 + 96x15 + 60x14 + 202x13 + 182x12 + 124x11 + 157x10 + 200x9 + 134x8 + 27x7 + 129x6 + 209x5 + 17x4 + 163x3 + 163x2 + 120x1 + 133

Discard the lead 0 term to get:

87x17 + 204x16 + 96x15 + 60x14 + 202x13 + 182x12 + 124x11 + 157x10 + 200x9 + 134x8 + 27x7 + 129x6 + 209x5 + 17x4 + 163x3 + 163x2 + 120x1 + 133

Use the terms of the remainder as the error correction codewords

The division has been performed 15 times, which is the number of terms in the message polynomial. This means that the division is complete and the terms of the above polynomial are the error correction codewords to use for the original message polynomial:

87  204  96  60  202  182  124  157  200  134  27  129  209  17  163  163  120  133