OFFSET
1,2
LINKS
Ludovic Schwob, Table of n, a(n) for n = 1..200
Ron M. Adin, Alexander Postnikov, and Yuval Roichman! Combinatorial Gelfand models, J. Algebra, 320(3):1311-1325, 2008.
Arvind Ayyer, Hiranya Kishore Dey, and Digjoy Paul, How large is the character degree sum compared to the character table sum for a finite group?, arXiv preprint arXiv:2406.06036 [math.RT], 2024. See p. 5.
Arvind Ayyer, Hiranya Kishore Dey, and Digjoy Paul, On the sum of the entries in a character table, Proceedings of the 36th Conference on Formal Power Series and Algebraic Combinatorics (Bochum), Séminaire Lotharingien de Combinatoire 91B (2024), Article #99, 12 pp.
J. B. Geloun and S. Ramgoolam, Counting Tensor Model Observables and Branched Covers of the 2-Sphere, arXiv preprint arXiv:1307.6490 [hep-th], 2013.
FORMULA
Let D(x) = Sum_{n>=0} (2n-1)!!*x^n = 1/(1 - x/(1 - 2x/(1 - 3x/...))) and R_r(x) = Sum_{n>=0} o_r(n)*x^n = 1/(1 - x - r*x^2/(1 - x - 2*r*x^2/(1 - x - 3*r*x^2/...))), where o_r(n) = Sum_{k=0..n/2} binomial(n, 2k)*(2k-1)!!*r^k. Then the generating function of this sequence is Sum_{n>=0} a(n)*x^n = Product_{i >= 1} (D(2ix^{4i}) * R_{2i-1}(x^{2i-1}). - Arvind Ayyer, Jun 11 2024
EXAMPLE
a(3) = 5 because the character table of S_3 is / 1 1 1 / 2 0 -1 / 1 -1 1 /.
MATHEMATICA
a[n_] := FiniteGroupData[{"SymmetricGroup", n}, "CharacterTable"] // Flatten // Total;
Table[an = a[n]; Print[n, " ", an]; an, {n, 1, 10}] (* Jean-François Alcover, Nov 03 2018 *)
PROG
(GAP) A082733 := n -> Sum(Sum(Irr(CharacterTable("Symmetric", n)))); # Eric M. Schmidt, Jul 03 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladeta Jovovic, May 20 2003
EXTENSIONS
More terms from Eric M. Schmidt, Jul 03 2012
STATUS
approved