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A030129 Number of nonisomorphic Steiner triple systems (STS's) S(2,3,n) on n points. 8
1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 2, 0, 80, 0, 0, 0, 11084874829 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,13

REFERENCES

L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 304.

CRC Handbook of Combinatorial Designs, 1996, p. 70.

LINKS

Table of n, a(n) for n=1..19.

P. Kaski and P. R. J. Ostergard (Patric.Ostergard(AT)hut.fi), The Steiner triple systems of order 19

Eric Weisstein's World of Mathematics, Steiner Triple System.

Index entries for sequences related to Steiner systems

CROSSREFS

Cf. A001201, A030128, A051390, A124118, A124119.

Sequence in context: A195209 A098276 A215880 * A012647 A012334 A012451

Adjacent sequences:  A030126 A030127 A030128 * A030130 A030131 A030132

KEYWORD

nonn,nice,hard

AUTHOR

Eric W. Weisstein

STATUS

approved

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Last modified December 10 13:38 EST 2016. Contains 279004 sequences.