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 A144254 #2 Mar 30 2012 17:25:32 %S A144254 1,2,1,3,4,3,4,10,18,10,5,20,63,80,42,6,35,168,360,420,210,7,56,378, %T A144254 1200,2310,2520,1199,8,84,756,3300,9240,16380,16786,7670,9,120,1386, %U A144254 7920,30030,76440,125895,122720,54224,10,165,2376,17160,84084,286650 %N A144254 Eigentriangle by rows, termwise products of A078812 and its eigensequence, A125274. %C A144254 Right border A144253 = A125274, the eigensequence of A078812: (1, 1, 3, 10, 42, 210, 1199,...). %C A144254 Row sums = A125274 shifted. %C A144254 Sum of row n terms = rightmost term of next row. %F A144254 Eigensequence by rows, T(n,k) = A078812(n,k) * A125274(k). %e A144254 First few rows of the triangle = %e A144254 1; %e A144254 2, 1; %e A144254 3, 4, 3; %e A144254 4, 10, 18, 10; %e A144254 5, 20, 63, 80, 42; %e A144254 6, 35, 168, 360, 420, 210; %e A144254 7, 56, 378, 1200, 2310, 2520, 1199; %e A144254 ... %e A144254 Triangle A078812 begins: %e A144254 1; %e A144254 2, 1; %e A144254 3, 4, 1; %e A144254 4, 10, 6, 1; %e A144254 5, 20, 21, 8, 1; %e A144254 ... %e A144254 Its eigensequence = A125274: (1, 1, 3, 10, 42, 210, 1199,...). %e A144254 Row 3 of triangle A144253 = termwise products of (4, 10, 6, 1) and (1, 1, 3, 10) = (4*1, 10*1, 6*3, 1*10). %Y A144254 A078812, Cf. A125274 %K A144254 nonn,tabl %O A144254 1,2 %A A144254 _Gary W. Adamson_, Sep 16 2008