

A106164


Number of indecomposable Type I but not Type II binary selfdual codes of length 2n.


2



0, 1, 0, 0, 0, 0, 1, 1, 1, 2, 6, 8, 19, 45, 148, 457, 2448, 20786
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OFFSET

0,10


REFERENCES

R. T. Bilous, Enumeration of binary selfdual codes of length 34, Preprint, 2005.
R. T. Bilous and G. H. J. van Rees, An enumeration of binary selfdual codes of length 32, Designs, Codes Crypt., 26 (2002), 6186.
J. H. Conway and V. S. Pless, On the enumeration of selfdual codes, J. Comb. Theory, A28 (1980), 2653.
V. S. Pless, The children of the (32,16) doubly even codes, IEEE Trans. Inform. Theory, 24 (1978), 738746.


LINKS

Table of n, a(n) for n=0..17.
G. Nebe, E. M. Rains and N. J. A. Sloane, SelfDual Codes and Invariant Theory, Springer, Berlin, 2006.
J. H. Conway, V. Pless and N. J. A. Sloane, The Binary SelfDual Codes of Length Up to 32: A Revised Enumeration, J. Comb. Theory, A28 (1980), 2653 (Abstract, pdf, ps, Table A, Table D).
E. M. Rains and N. J. A. Sloane, Selfdual codes, pp. 177294 of Handbook of Coding Theory, Elsevier, 1998 (Abstract, pdf, ps).


CROSSREFS

Cf. A003178, A003179, A106162A106167.
Sequence in context: A323859 A098092 A221316 * A216205 A072230 A028332
Adjacent sequences: A106161 A106162 A106163 * A106165 A106166 A106167


KEYWORD

nonn,hard,more


AUTHOR

N. J. A. Sloane, May 09 2005


EXTENSIONS

a(34) computed by N. J. A. Sloane, based on data in Bilous's paper, Sep 06 2005


STATUS

approved



