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 A131776 #7 Mar 04 2022 01:25:48 %S A131776 1,4,1,1,4,1,4,-2,8,1,1,4,3,8,1,4,-5,16,0,12,1,1,4,2,16,9,12,1,4,-8, %T A131776 24,-10,40,6,16,1,1,4,-2,24,15,40,19,16,1,4,-11,32,-32,84,-3,80,16,20, %U A131776 1 %N A131776 4*A065941 - 3*A049310. %C A131776 Row sums = A022095, a Fibonacci-like sequence starting (1, 5, 6, 11, 17, 28, ...). %F A131776 4*A065941 - 3*A049310 as infinite lower triangular matrices. %e A131776 First few rows of the triangle: %e A131776 1; %e A131776 4, 1; %e A131776 1, 4, 1; %e A131776 4, -2, 8, 1; %e A131776 1, 4, 3, 8, 1; %e A131776 4, -5, 16, 0, 12, 1; %e A131776 1, 4, 2, 16, 9, 12, 1; %e A131776 ... %Y A131776 Cf. A065941, A049310, A022095, A131774, A131775, A131777, A131778. %K A131776 tabl,sign %O A131776 1,2 %A A131776 _Gary W. Adamson_, Jul 14 2007