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 A172543 #6 Apr 11 2017 16:38:02 %S A172543 0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,20922789888000, %T A172543 10268902998771351157327104000, %U A172543 2767806480542211571651550187279222472704000 %N A172543 Number of n X n 0..1 arrays with row sums 15 and column sums 15. %H A172543 R. H. Hardin, <a href="/A172543/b172543.txt">Table of n, a(n) for n=1..20</a> %Y A172543 Column k=15 of A008300. %K A172543 nonn %O A172543 1,16 %A A172543 _R. H. Hardin_, Feb 06 2010