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 A274691 #37 May 19 2024 08:11:52 %S A274691 1,1,4,7,19,33,77,135,218,392,798,1312,2381,4107,6639,11722,15869, %T A274691 26333,45115,69168,106213,170710,244042,384991,592859,895944,1326012, %U A274691 2055454,2884762,4466493,6553384,9798596,13336991,20192347,28680574,41695293,59766105,86344867 %N A274691 Number of odd entries in the character table of the symmetric group S_n. %H A274691 Hugo Pfoertner, <a href="/A274691/b274691.txt">Table of n, a(n) for n = 0..76</a> %H A274691 Alexander R. Miller, <a href="https://www.mat.univie.ac.at/~miller/ARMillerEvenOddNote.pdf">On parity and characters of symmetric groups</a>, preprint. %H A274691 Alexander R. Miller, <a href="https://doi.org/10.1016/j.jcta.2018.11.001">On parity and characters of symmetric groups</a>, J. Combin. Theory Ser. A 162 (2019), 231-240. Gives terms for n <= 76. %e A274691 For n = 2, all four character values are 1 or -1, so a(2) = 4. %p A274691 with(combinat): %p A274691 a:= n-> add(`if`(i[]::odd, 1, 0), i=entries(character(n))): %p A274691 seq(a(n), n=0..15); # _Alois P. Heinz_, Jul 10 2016 %Y A274691 Cf. A001255, A006907, A335686. %K A274691 nonn %O A274691 0,3 %A A274691 _Richard Stanley_, Jul 02 2016 %E A274691 More terms from _Alois P. Heinz_, Jul 10 2016 %E A274691 Further terms from Miller (2019) added by _N. J. A. Sloane_, Jul 07 2020