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 A147768 #14 Jul 29 2023 03:28:38 %S A147768 1,-1,1,1,-1,1,0,1,-1,1,1,0,1,-1,1,0,1,0,1,-1,1,2,0,1,0,1,-1,1,0,2,0, %T A147768 1,0,1,-1,1,3,0,2,0,1,0,1,-1,1,1,3,0,2,0,1,0,1,-1,1,4,1,3,0,2,0,1,0,1, %U A147768 -1,1,2,4,1,3,0,2,0,1,0,1,-1,1 %N A147768 Triangle read by rows: A000012^(-2) * A027293 as infinite lower triangular matrices. %C A147768 Row sums = A002865, (1, 0, 1, 1, 2, 2, 4, 4, 7, 8,...). %C A147768 This triangle is the lower right half of a Toeplitz matrix. Each column of this triangle has the form [1, -1] U A053445. - _Georg Fischer_, Jul 28 2023 %F A147768 A000012^(-1) is the pairwise difference operator, and A027293 = a triangle with A000041 in every column. %F A147768 Equals A185018 * A027293 since A000012^2 = A004736 and A004736^(-1) = A185018. - _Georg Fischer_, Jul 28 2023 %e A147768 First few rows of the triangle = %e A147768 1; %e A147768 -1, 1; %e A147768 1, -1, 1; %e A147768 0, 1, -1, 1; %e A147768 1, 0, 1, -1, 1; %e A147768 0, 1, 0, 1, -1, 1; %e A147768 2, 0, 1, 0, 1, -1, 1; %e A147768 0, 2, 0, 1, 0, 1, -1, 1; %e A147768 3, 0, 2, 0, 1, 0, 1, -1, 1; %e A147768 1, 3, 0, 2, 0, 1, 0, 1, -1, 1; %e A147768 4, 1, 3, 0, 2, 0, 1, 0, 1, -1, 1; %e A147768 2, 4, 1, 3, 0, 2, 0, 1, 0, 1, -1, 1; %e A147768 ... %Y A147768 Cf. A000012, A000041, A002865, A004736, A027293, A053445, A185018. %K A147768 tabl,sign %O A147768 0,22 %A A147768 _Gary W. Adamson_, Nov 11 2008