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 A208447 #32 Sep 24 2018 14:09:07 %S A208447 1,1,1,1,1,2,1,1,2,3,1,1,2,4,5,1,1,2,6,10,7,1,1,2,10,24,26,11,1,1,2, %T A208447 18,64,120,76,15,1,1,2,34,180,596,720,232,22,1,1,2,66,520,3060,8056, %U A208447 5040,764,30,1,1,2,130,1524,16076,101160,130432,40320,2620,42 %N A208447 Sum of the k-th powers of the numbers of standard Young tableaux over all partitions of n; square array A(n,k), n>=0, k>=0, read by antidiagonals. %H A208447 Alois P. Heinz, <a href="/A208447/b208447.txt">Antidiagonals n = 0..50</a> %H A208447 Wikipedia, <a href="https://en.wikipedia.org/wiki/Young_tableau">Young tableau</a> %e A208447 A(3,2) = 1^2 + 2^2 + 1^2 = 6 = 3! because 3 has partitions 111, 21, 3 with 1, 2, 1 standard Young tableaux, respectively: %e A208447 .111. . 21 . . . . . . . . 3 . . . . %e A208447 +---+ +------+ +------+ +---------+ %e A208447 | 1 | | 1 2 | | 1 3 | | 1 2 3 | %e A208447 | 2 | | 3 .--+ | 2 .--+ +---------+ %e A208447 | 3 | +---+ +---+ %e A208447 +---+ %e A208447 Square array A(n,k) begins: %e A208447 1, 1, 1, 1, 1, 1, 1, ... %e A208447 1, 1, 1, 1, 1, 1, 1, ... %e A208447 2, 2, 2, 2, 2, 2, 2, ... %e A208447 3, 4, 6, 10, 18, 34, 66, ... %e A208447 5, 10, 24, 64, 180, 520, 1524, ... %e A208447 7, 26, 120, 596, 3060, 16076, 86100, ... %e A208447 11, 76, 720, 8056, 101160, 1379176, 19902600, ... %p A208447 h:= proc(l) local n; n:=nops(l); add(i, i=l)! /mul(mul(1+l[i]-j %p A208447 +add(`if`(l[k]>=j, 1, 0), k=i+1..n), j=1..l[i]), i=1..n) %p A208447 end: %p A208447 g:= proc(n, i, k, l) `if`(n=0, h(l)^k, `if`(i<1, 0, g(n, i-1, k, l) %p A208447 + `if`(i>n, 0, g(n-i, i, k, [l[], i])))) %p A208447 end: %p A208447 A:= (n, k)-> `if`(n=0, 1, g(n, n, k, [])): %p A208447 seq(seq(A(n, d-n), n=0..d), d=0..10); %t A208447 h[l_] := With[{n = Length[l]}, Sum[i, {i, l}]! / Product[Product[1 + l[[i]] - j + Sum [If[l[[k]] >= j, 1, 0], { k, i+1, n}], {j, 1, l[[i]]}], {i, 1, n}]]; g[n_, i_, k_, l_] := If[n == 0, h[l]^k, If[i < 1, 0, g[n, i-1, k, l] + If[i > n, 0, g[n-i, i, k, Append[l, i]]]]]; a [n_, k_] := If[n == 0, 1, g[n, n, k, {}]]; Table[Table[a[n, d-n], {n, 0, d}], {d, 0, 10}] // Flatten (* _Jean-François Alcover_, Dec 11 2013, translated from Maple *) %Y A208447 Columns 0-10 give: A000041, A000085, A000142, A130721, A129627, A218432, A218433, A218434, A218435, A218436, A218437. %Y A208447 Rows 0+1, 2, 3 give: A000012, A007395, A052548. %Y A208447 Main diagonal gives A319607. %K A208447 nonn,tabl %O A208447 0,6 %A A208447 _Alois P. Heinz_, Feb 26 2012