This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A051391 #18 Feb 03 2020 03:14:11 %S A051391 1,1,1,1,2,80,11084874829 %N A051391 Number of nonisomorphic Steiner triple systems (STS's) S(2,3,v) on v = 6n+1 or 6n+3 points. %D A051391 L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 304. %D A051391 CRC Handbook of Combinatorial Designs, 1996, p. 70. %H A051391 Petteri Kaski and Patric R. J. Östergård, <a href="http://www.tcs.hut.fi/~pkaski/sts19.ps">The Steiner triple systems of order 19</a> %H A051391 Petteri Kaski and Patric R. J. Östergård, <a href="https://doi.org/10.1090/S0025-5718-04-01626-6">The Steiner triple systems of order 19</a>, Mathematics of Computation, Vol. 73, No. 248 (Oct., 2004), pp. 2075-2092. %H A051391 <a href="/index/St#Steiner">Index entries for sequences related to Steiner systems</a> %e A051391 There are 2 nonisomorphic STS's on 13 points. %Y A051391 Indexed by A047241. Cf. A001201, A030128, A030129, A051390, A124118, A124119. %K A051391 nonn,nice,hard %O A051391 1,5 %A A051391 _N. J. A. Sloane_