%I #21 Sep 14 2021 01:11:56
%S 1,1,1,2,3,5,10,21,55,245,3427
%N Number of self-dual codes of length 2n over GF(4).
%H J. Conway, V. Pless and N. Sloane, <a href="https://doi.org/10.1109/TIT.1979.1056047">Self-dual codes over GF(3) and GF(4)of length not exceeding 16</a>, IEEE Trans. Information Theory 25 312-322 1979.
%H Masaaki Harada and Akihiro Munemasa, <a href="https://doi.org/10.1109/TIT.2011.2134330">Classification of quaternary Hermitian self-dual codes of length 20</a>, IEEE Transactions on Information Theory, 57 (2011), 3758-3762; arXiv:<a href="https://arxiv.org/abs/1012.0898">1012.0898</a> [math.CO], 2010.
%H W. C. Huffman, <a href="http://dx.doi.org/10.1016/j.ffa.2005.05.012">On the classification and enumeration of self-dual codes</a>, Finite Fields Applic. 11 (2005), 451-490.
%H F. J. MacWilliams, A. M. Odlyzko, N. J. A. Sloane and H. N. Ward, <a href="https://doi.org/10.1016/0097-3165(78)90021-3">Self-Dual Codes over GF(4)</a>, J. Combin. Theory, A 25 288-318 1978.
%H G. Nebe, E. M. Rains and N. J. A. Sloane, <a href="http://neilsloane.com/doc/cliff2.html">Self-Dual Codes and Invariant Theory</a>, Springer, Berlin, 2006.
%H E. M. Rains and N. J. A. Sloane, Self-dual codes, pp. 177-294 of Handbook of Coding Theory, Elsevier, 1998 (<a href="http://neilsloane.com/doc/self.txt">Abstract</a>, <a href="http://neilsloane.com/doc/self.pdf">pdf</a>, <a href="http://neilsloane.com/doc/self.ps">ps</a>).
%K nonn,hard,more
%O 0,4
%A _N. J. A. Sloane_
%E a(9)-a(10) from Harada & Munemasa added by _Andrey Zabolotskiy_, Sep 13 2021