A002885 Number of cyclic Steiner triple systems of order 2n+1. (Formerly M0032 N0393)

1, 1, 0, 1, 0, 0, 1, 2, 0, 4, 7, 0, 12, 8, 0, 80, 84, 0, 820, 798, 0, 9508, 11616, 0, 157340, 139828, 0, 3027456, 2353310

Offset

0,8

References

C. J. Colbourn and A. Rosa: Triple Systems, Clarendon Press (Oxford) 1999

J. Doyen, Problem 30, p. 504 of R. K. Guy et al., editors, Combinatorial Structures and Their Applications (Proceedings Calgary Conference Jun 1969), Gordon and Breach, NY, 1970.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

Table of n, a(n) for n=0..28.

Index entries for sequences related to Steiner systems

Crossrefs

Sequence in context: A317965 A369025 A190791 * A344769 A011121 A255643

Adjacent sequences: A002882 A002883 A002884 * A002886 A002887 A002888

Keyword

nonn,more

Author

N. J. A. Sloane

Extensions

More terms from Michael Steyer (m.steyer(AT)osram.de), Jan 27 2005

Status

approved