Optimal Insertion-Deletion Correcting Codes

Insertion-deletion correcting codes are designed to correct insertions and deletions of characters. Insertion-deletion distance measures the minimum number of insertions and/or deletions required to transform one word into another.

Define Dq(n,d) to be the number of codewords in an optimal q-ary code of length n and minimum insertion-deletion distance d. We consider the variable-length case, in which n is the length of the longest codeword.

The earliest versions of the tables below appeared in: S.Baker, R.Flack and S.Houghten, "Optimal Variable-Length Insertion-Deletion Correcting Codes and Edit Metric Codes", Congressus Numerantium 186 (2008), 65-80. For each of the tables, upper and lower bounds are provided where exact values are not known.

Table of Bounds on Optimal Binary Insertion-Deletion Correcting Codes

 n\d 1 2 3 4 5 6 7 8 9 10 11 12
 1 3 2 1 1 1 1 1 1 1 1 1 1
 2 7 5 2 2 1 1 1 1 1 1 1 1
 3 15 10 3 2 2 2 1 1 1 1 1 1
 4 31 21 6 5 2 2 2 2 1 1 1 1
 5 63 42 9 7 3 2 2 2 2 2 1 1
 6 127 85 15 12 6 5 2 2 2 2 2 2
 7 255 170 25-31 18 7 6 3 2 2 2 2 2
 8 511 341 41-63 31-37 10 8 6 5 2 2 2 2
 9 1023 682 67-127 49-75 16-21 13 7 6 3 2 2 2
 10 2047 1365 116-255 83-151 20-43 18-27 8 7 6 5 2 2
 11 4095 2730 205-511 143-303 30-87 24-55 11-17 9 6 6 3 2
 12 8191 5461 360-1023 255-607 45-175 36-111 15-35 14-19 8 7 6 5

Table of Bounds on Optimal Ternary Insertion-Deletion Correcting Codes

 n\d 1 2 3 4 5 6 7 8 9 10 11 12
 1 4 3 1 1 1 1 1 1 1 1 1 1
 2 13 10 3 3 1 1 1 1 1 1 1 1
 3 40 30 6 5 3 3 1 1 1 1 1 1
 4 121 91 13 12 4 3 3 3 1 1 1 1
 5 364 273 29-40 25-37 7 6 3 3 3 3 1 1
 6 1093 820 67-121 55-112 14 12 5 5 3 3 3 3
 7 3280 2460 158-364 122-337 24-43 21-37 8 7 4 3 3 3
 8 9841 7381 396-1093 310-1012 43-130 36-112 15-25 13-22 6 6 3 3
 9 29524 22143 1022-3280 792-3037 92-391 75-337 20-76 18-67 9-19 8-19 5 5
 10 88573 66430 2678-9841 2064-9112 187-1174 152-1012 32-229 28-202 13-58 13-58 7-16 7-16

If you have improvements, comments, etc, please e-mail houghten@brocku.ca

This page last modified 5th August 2008
© Copyright Sheridan Houghten, 2005-2008