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 A131416 #2 Mar 30 2012 17:25:22 %S A131416 1,4,3,8,8,5,13,14,12,7,19,21,20,16,9,26,29,29,26,20,11,34,38,39,37, %T A131416 32,24,13,43,48,50,49,45,38,28,15,53,59,62,62,59,53,44,32,17,64,71,75, %U A131416 76,74,69,61,50,36,19 %N A131416 (A000012 * A002260) + (A002260 * A000012) - A000012. %C A131416 Left column = A034856: (1, 4, 8, 13, 19, 26, 34,...). Row sums = A127735: (1, 7, 21, 46, 85...). %F A131416 (A000012 * A002260) + (A002260 * A000012) - A000012; as infinite lower triangular matrices. %e A131416 First few rows of the triangle are: %e A131416 1; %e A131416 4, 3; %e A131416 8, 8, 5; %e A131416 13, 14, 12, 7; %e A131416 19, 21, 20, 16, 9; %e A131416 26, 29, 29, 26, 20, 11; %e A131416 ... %Y A131416 Cf. A002260, A034856, A127735, A000012. %K A131416 nonn,tabl %O A131416 1,2 %A A131416 _Gary W. Adamson_, Jul 08 2007