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Sum of the 4th powers of the degrees of irreducible representations of S_n, the symmetric group on n letters.
2

%I #24 May 18 2017 03:48:23

%S 1,2,18,180,3060,101160,3807720,174986280,10699554600,927701102160,

%T 95030461809360,10905467528783520,1431935974242053280,

%U 222906109589537774400,42471495822490670295360,9447237366839585591438160,2329156499421828313498781520

%N Sum of the 4th powers of the degrees of irreducible representations of S_n, the symmetric group on n letters.

%C a(n) is also the sum of the fourth powers of the numbers of standard Young tableaux over all partitions of n. - _Thotsaporn Thanatipanonda_, Feb 25 2012

%H Alois P. Heinz, <a href="/A129627/b129627.txt">Table of n, a(n) for n = 1..60</a>

%H Thotsaporn Thanatipanonda, <a href="/A129627/a129627.txt">Maple code for A129627</a>

%t 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}]];

%t g[n_, i_, k_, l_] := g[n, i, l, k] = 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]]]]];

%t a[n_] := If[n == 0, 1, g[n, n, 4, {}]];

%t Table[a[n], {n, 1, 20}] (* _Jean-François Alcover_, May 18 2017, after _Alois P. Heinz_ *)

%o (GAP) List([1..20],n->Sum(List(Irr(CharacterTable("Symmetric",n)), x->x[1]^4)));

%Y Cf. A000142, A000085.

%Y Column k=4 of A208447. - _Alois P. Heinz_, Feb 28 2012

%K nonn

%O 1,2

%A _Dmitrii Pasechnik_, May 30 2007