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 A035529 #21 Aug 07 2024 09:18:54 %S A035529 1,6,1,42,12,1,315,120,18,1,2457,1134,234,24,1,19656,10458,2673,384, %T A035529 30,1,160056,95256,28539,5148,570,36,1,1320462,861597,292572,62532, %U A035529 8775,792,42,1,11003850,7760610,2920347,713664,119565,13770,1050,48,1 %N A035529 A convolution triangle of numbers obtained from A034171. %C A035529 a(n,1)= A034171(n-1); a(n,m)=: s2(4; n,m), generalizing s2(2; n,m) := A007318(n-1,m-1) (Pascal), s2(3; n,m) := A035324(n,m). %H A035529 Wolfdieter Lang, <a href="http://www.cs.uwaterloo.ca/journals/JIS/index.html">On generalizations of Stirling number triangles</a>, J. Integer Seqs., Vol. 3 (2000), #00.2.4. %F A035529 a(n+1, m) = 3*(3*n+m)*a(n, m)/(n+1) + m*a(n, m-1)/(n+1), n >= m >= 1; a(n, m) := 0, n<m; a(n, 0) := 0; a(1, 1)=1. %F A035529 G.f. for column m: ((-1+(1-9*x)^(-1/3))/3)^m. %e A035529 Triangle begins: %e A035529 1, %e A035529 6, 1; %e A035529 42, 12, 1; %e A035529 315, 120, 18, 1; %e A035529 2457, 1134, 234, 24, 1; %e A035529 19656, 10458, 2673, 384, 30, 1; %e A035529 ... %t A035529 a[n_, m_] /; n - 1 >= m >= 1 := (m*a[n - 1, m - 1])/n + (3*(m + 3*(n - 1))*a[n - 1, m])/n; a[n_, m_] /; n < m = 0; a[n_, 0] = 0; a[n_, n_] = 1; Flatten[Table[a[n, m], {n, 1, 9}, {m, 1, n}]] (* _Jean-François Alcover_, Jul 10 2012, from formula *) %Y A035529 Cf. A034171, A007318, A035324. %Y A035529 Row sums: A049028(n), n >= 1. %K A035529 easy,nice,nonn,tabl %O A035529 1,2 %A A035529 _Wolfdieter Lang_