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 A104560 #3 Mar 30 2012 18:36:45
%S A104560 1,-1,1,1,-2,1,-2,5,-4,1,6,-16,15,-6,1,-30,81,-79,36,-9,1,204,-552,
%T A104560 543,-256,72,-12,1,-1944,5262,-5184,2461,-712,132,-16,1,23340,-63180,
%U A104560 62260,-29596,8615,-1640,220,-20,1,-360060,974670,-960520,456700,-133091,25475,-3500,350,-25,1,6692280,-18115800
%N A104560 Matrix inverse of triangle A104559, read by rows.
%C A104560 Column 0 is A104561.
%e A104560 Triangle begins:
%e A104560 1;
%e A104560 -1,1;
%e A104560 1,-2,1;
%e A104560 -2,5,-4,1;
%e A104560 6,-16,15,-6,1;
%e A104560 -30,81,-79,36,-9,1;
%e A104560 204,-552,543,-256,72,-12,1;
%e A104560 -1944,5262,-5184,2461,-712,132,-16,1;
%e A104560 23340,-63180,62260,-29596,8615,-1640,220,-20,1;
%e A104560 -360060,974670,-960520,456700,-133091,25475,-3500,350,-25,1; ...
%o A104560 (PARI) {T(n,k)=local(M);M=matrix(n+1,n+1,m,j,if(m>=j, binomial(m-1-(j-1)\2,j\2)*binomial(m-1-j\2,(j-1)\2))); return((M^-1)[n+1,k+1])}
%Y A104560 Cf. A104559, A104561.
%K A104560 sign,tabl
%O A104560 0,5
%A A104560 _Paul D. Hanna_, Mar 16 2005