This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A323357 #7 Feb 17 2019 09:55:25 %S A323357 1,1,1,2,2,3,4,7,9,16,23,42,68,94,124,159,187,212 %N A323357 Number of binary self-dual codes of length 2n (up to permutation equivalence) that have a unique automorphism group size. %C A323357 Two codes are said to be permutation equivalent if permuting the columns of one code results in the other code. %C A323357 If permuting the columns of a code results in the same identical code the permutation is called an automorphism. %C A323357 The automorphisms of a code form a group called the automorphism group. %C A323357 Some codes have automorphism groups that contain the same number of elements. There are situations, both trivial and otherwise, that codes of different lengths can have the same size automorphism groups. %C A323357 Some codes have automorphism group sizes that are unique to the code. This sequence only compares automorphism group sizes for codes with the same length. %H A323357 W. Cary Huffman and Vera Pless, <a href="https://doi.org/10.1017/CBO9780511807077">Fundamentals of Error Correcting Codes</a>, Cambridge University Press, 2003, Pages 338-393. %e A323357 There are a(18) = 212 binary self-dual codes (up to permutation equivalence) of length 2*18 = 36 that have a unique automorphism group size. %Y A323357 For self-dual codes see A028362, A003179, A106162, A028363, A106163, A269455, A120373; for automorphism groups see A322299, A322339. %K A323357 nonn,more %O A323357 1,4 %A A323357 _Nathan J. Russell_, Jan 12 2019