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 A128496 #4 Mar 31 2012 13:20:13 %S A128496 1,2,4,9,20,50,125,324,840,2195,5736,15012,39289,102854,269260,704925, %T A128496 1845500,4831574,12649205,33116040,86698896,226980647,594243024, %U A128496 1555748424,4073002225,10663258250,27916772500,73087059249,191344405220 %N A128496 Row sums of unsigned triangle |A128495|=|S(2;n,m)| (sums of squares of Chebyshev's S-polynomials). %F A128496 a(n)=sum(|A128495(n,m)|,m=0..n). %Y A128496 Cf. A004523 (looks like signed row sums). %K A128496 nonn,easy %O A128496 0,2 %A A128496 _Wolfdieter Lang_ Apr 04 2007