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 A115452 #2 Mar 30 2012 18:59:13 %S A115452 1,2,-1,2,-3,1,2,-3,3,-1,0,0,2,-3,1,-2,3,-1,-2,3,-1,0,0,0,0,2,-3,1,2, %T A115452 -3,3,-1,0,-2,3,-1,0,0,0,0,0,0,2,-3,1,0,0,-2,3,-1,0,0,-2,3,-1,0,0,0,0, %U A115452 0,0,0,0,2,-3,1,-2,3,-1,-2,3,-1,0,0,0,-2,3,-1,0,0,0,0,0,0,0,0,0,0,2,-3,1 %N A115452 A Fredholm-Rueppel related triangle. %C A115452 Inverse of A115450. Row sums are Fredholm-Rueppel sequence A036987. %F A115452 Inverse of (1/((1-x)(1-2x)), -x)-(x/((1-x)(1-2x)), -x^2) (expressed in the notation of Riordan arrays). %e A115452 Triangle begins %e A115452 1, %e A115452 2, -1, %e A115452 2, -3, 1, %e A115452 2, -3, 3, -1, %e A115452 0, 0, 2, -3, 1, %e A115452 -2, 3, -1, -2, 3, -1, %e A115452 0, 0, 0, 0, 2, -3, 1, %e A115452 2, -3, 3, -1, 0, -2, 3, -1, %e A115452 0, 0, 0, 0, 0, 0, 2, -3, 1, %e A115452 0, 0, -2, 3, -1, 0, 0, -2, 3, -1, %e A115452 0, 0, 0, 0, 0, 0, 0, 0, 2, -3, 1, %e A115452 -2, 3, -1, -2, 3, -1, 0, 0, 0, -2, 3, -1, %e A115452 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, -3, 1 %K A115452 sign,tabl %O A115452 0,2 %A A115452 _Paul Barry_, Jan 22 2006