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 A147294 #4 Jun 02 2025 00:42:41 %S A147294 1,1,1,2,3,2,5,9,10,7,14,28,40,49,31,42,90,150,245,279,162,132,297, %T A147294 550,1078,1674,1782,968,429,1001,2002,4459,8463,12474,12584,6481,1430, %U A147294 3432,7280,17836,39060,71280,100672,97215,47893 %N A147294 Eigentriangle, row sums = A125275. %C A147294 Row sums = A125275 starting with offset 1: (1, 2, 7, 31, 162, 968,...). %C A147294 Left border = A000108, right border = A125275. %C A147294 Sum of n-th row terms = rightmost term of next row. %F A147294 A147294 = Triangle A039599 * (A125275 * 0^(n-k)); where (A125275 * 0^(n-k)) = an infinite lower triangular matrix with A125275: (1, 1, 2, 7, 31, 162,...) as the main diagonal and the rest zeros. %e A147294 First few rows of the triangle = %e A147294 1; %e A147294 1, 1; %e A147294 2, 3, 2; %e A147294 5, 9, 10, 7; %e A147294 14, 28, 40, 49, 31; %e A147294 42, 90, 150, 245, 279, 162; %e A147294 132, 297, 550, 1078, 1674, 1782, 968; %e A147294 429, 1001, 2002, 4459, 8463, 12474, 12584, 6481; %e A147294 1430, 3432, 7280, 17836, 39060, 71280, 100672, 97215, 47893; %e A147294 ... %e A147294 Row 4 = (5, 9, 10, 7) = termwise products of (5, 9, 5, 1) and (1, 1, 2, 7) %Y A147294 A125275, Cf. A000108, A039599 %K A147294 eigen,nonn,tabl %O A147294 1,4 %A A147294 _Gary W. Adamson_, Nov 05 2008