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 A131254 #4 Feb 18 2022 22:43:00 %S A131254 1,2,1,4,3,1,7,6,4,1,12,11,9,5,1,20,19,17,13,6,1,33,32,30,26,18,7,1, %T A131254 54,53,51,47,39,24,8,1,88,87,85,81,73,57,31,9,1,143,142,140,136,128, %U A131254 112,81,39,10,1 %N A131254 A004070 * A000012. %C A131254 Left column = A000071, (Fibonacci numbers - 1) starting with F(3): (1, 2, 4, 7, 12, 20, ...). %F A131254 A004070 * A000012 as infinite lower triangular matrices. Partial row sums of A004070 starting from the right. %e A131254 First few rows of the triangle: %e A131254 1; %e A131254 2, 1; %e A131254 4, 3, 1; %e A131254 7, 6, 4, 1; %e A131254 12, 11, 9, 5, 1; %e A131254 20, 19, 17, 13, 6, 1; %e A131254 33, 32, 30, 26, 18, 7, 1; %e A131254 ... %e A131254 Row 3 = (7, 6, 4, 1) = partial sums starting from the right of (1, 2, 3, 1), being row 3 of A004070. %Y A131254 Cf. A004070, A000012, A000071. %K A131254 nonn,tabl %O A131254 0,2 %A A131254 _Gary W. Adamson_, Jun 23 2007