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 A156065 #2 Mar 30 2012 18:59:22 %S A156065 1,1,0,-1,2,6,-11,-35,73,232,-516,-1646,3825,12239,-29344,-94137, %T A156065 231050,742825,-1856679,-5980056,15166101,48922556,-125557710, %U A156065 -405553786,1051197507,3399234751 %N A156065 Diagonal sums of inverse of Riordan array (1/(1-x^4),x/(1-x^4)). %C A156065 When aerated gives the diagonal sums of A156064. %K A156065 sign %O A156065 0,5 %A A156065 _Paul Barry_, Oct 20 2009