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 A189865 #6 Sep 12 2015 11:00:25 %S A189865 1,0,0,2,10,0,0,4,32,76,196,632,3368,12532,79788,468286,2815088, %T A189865 18287968,126620984,938037664,7232141830,59774887344 %N A189865 Number of ways to place n nonattacking composite pieces queen + leaper[1,4] on an n X n chessboard. %C A189865 In fairy chess the leaper [1,4] is called a giraffe. %C A189865 a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+1)-p(i)|<>4 AND |p(j+4)-p(j)|<>1 AND |p(m+k)-p(m)|<>k for all i>=1, j>=1, m>=1, k>=1, i+1<=n, j+4<=n, m+k<=n %H A189865 V. Kotesovec, <a href="https://oeis.org/wiki/User:Vaclav_Kotesovec">Number of ways of placing non-attacking queens, kings, bishops and knights</a> (in English and Czech) %H A189865 Wikipedia, <a href="http://en.wikipedia.org/wiki/Fairy_chess_piece">Fairy chess piece</a> %Y A189865 Cf. A051223, A189864, A189563 %K A189865 nonn,hard %O A189865 1,4 %A A189865 _Vaclav Kotesovec_, Apr 29 2011