%I A030128
%S A030128 1,0,1,0,0,0,30,0,840,0,0,0,1197504000,0,60281712691200,0,0,0,
%T A030128 1348410350618155344199680000
%N A030128 Steiner triple systems (STS's) on n elements.
%D A030128 L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 304.
%D A030128 CRC Handbook of Combinatorial Designs, 1996, p. 70.
%H A030128 P. Kaski and P. R. J. \"Osterg{\aa}rd (Patric.Ostergard(AT)hut.fi), <a 
               href="http://www.tcs.hut.fi/~pkaski/sts19.ps">The Steiner triple 
               systems of order 19</a>
%H A030128 <a href="Sindx_St.html#Steiner">Index entries for sequences related to 
               Steiner systems</a>
%Y A030128 Cf. A001201, A030129, A051390.
%Y A030128 Sequence in context: A124992 A023926 A022068 this_sequence A137348 A137737 
               A062513
%Y A030128 Adjacent sequences: A030125 A030126 A030127 this_sequence A030129 A030130 
               A030131
%K A030128 nonn,nice,hard
%O A030128 1,7
%A A030128 N. J. A. Sloane (njas(AT)research.att.com).