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 A039910 #8 Oct 30 2015 10:18:19
%S A039910 1,0,1,0,-2,1,0,12,-6,1,0,-132,66,-12,1,0,2280,-1140,210,-20,1,0,
%T A039910 -56760,28380,-5240,510,-30,1,0,1923600,-961800,177660,-17360,1050,
%U A039910 -42,1,0,-85149960,42574980,-7864920,769090,-46760,1932,-56,1
%N A039910 Lower triangular matrix T = Pascal lower triangular matrix divided on the left by its entry-square.
%C A039910 Reference is a solution to a problem of I. Gessel.
%D A039910 "Inverse of a Combinatorial Matrix", Dave Callan, American Mathematical Monthly, Vol. 95 (1988), pp. 770-771.
%F A039910 T=Inverse matrix of {a_ij}:{binomial(i, j)*binomial(j, j-i)}=[ A008459 ]^(-1)*[ A007318 ]
%e A039910 1;
%e A039910 0,1;
%e A039910 0,-2,1;
%e A039910 0,12,-6,1;
%e A039910 0,-132,66,-12,1;
%e A039910 etc.
%Y A039910 A007318, A008459.
%K A039910 sign,tabl
%O A039910 0,5
%A A039910 _Len Smiley_