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 A055905 #3 Mar 30 2012 17:37:11 %S A055905 1,-1,1,2,-3,1,-5,9,-5,1,12,-25,19,-7,1,-17,48,-55,32,-9,1,-62,60,60, %T A055905 -96,48,-11,1,677,-1229,639,7,-149,67,-13,1,-2840,6435,-5565,2275, %U A055905 -165,-215,89,-15,1,-1451,-6189,18556,-15974,5778,-523,-295,114,-17,1 %N A055905 Matrix inverse of triangle A055898. %e A055905 1; -1,1; 2,-3,1; -5,9,-5,1; 12,-25,19,-7,1; ... %Y A055905 Column 0 in A055906. %K A055905 sign,tabl %O A055905 0,4 %A A055905 _Christian G. Bower_, Jun 13 2000