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 A139633 #3 Mar 03 2013 14:27:44 %S A139633 1,1,1,1,2,3,1,3,9,2,1,4,18,8,5,1,5,30,20,25,3,1,6,45,40,75,18,7,1,7, %T A139633 63,70,175,63,49,4,1,8,84,112,350,168,196,32,9,1,9,108,168,630,378, %U A139633 588,144,81,5,1,10,135,240,1050,756,1470,480,405,50,11,1,11,165,330,1650,1386 %N A139633 Triangle read by rows: binomial transform of a diagonalized matrix of A026741. %C A139633 Row sums = A084860: (1, 2, 6, 15, 36, 84, 192,...). %F A139633 Let X = a diagonalized matrix of A026741: [1; 0,1; 0,0,3; 0,0,0,2;], where the first few nonzero terms of A026741 are (1, 1, 3, 2, 5, 3, 7,...). The triangle = A007318 * X. %e A139633 First few rows of the triangle are: %e A139633 1; %e A139633 1, 1; %e A139633 1, 2, 3; %e A139633 1, 3, 9, 2; %e A139633 1, 4, 18, 8, 5; %e A139633 1, 5, 30, 20, 25, 3; %e A139633 1, 6, 45, 40, 75, 18, 7; %e A139633 1, 7, 63, 70, 175, 63, 49, 4; %e A139633 ... %Y A139633 Cf. A026741, A084860. %K A139633 nonn,tabl %O A139633 1,5 %A A139633 _Gary W. Adamson_ and _Roger L. Bagula_, Apr 27 2008