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 A159972 #4 Oct 25 2012 14:53:03 %S A159972 1,-1,0,2,-7,21,-63,195,-624,2054,-6916,23712,-82498,290510,-1033410, %T A159972 3707850,-13402695,48760365,-178405155,656043855,-2423307045, %U A159972 8987427465,-33453694485,124936258125,-467995871775,1757900019099,-6619846420551 %N A159972 Row sums of number triangle A159971. %F A159972 G.f.: (2c(-x)-1)/(1-xc(-x)^3)=(1-x+xc(-x))/(1+x)=(1-2x+sqrt(1+4x))/(2(1+x)), c(x) the g.f. of A000108. %F A159972 Apparently n*a(n) +(5*n-6)*a(n-1) +2*(2*n-3)*a(n-2)=0. - _R. J. Mathar_, Oct 25 2012 %K A159972 easy,sign %O A159972 0,4 %A A159972 _Paul Barry_, Apr 28 2009