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 A290138 #28 Nov 27 2024 16:46:29 %S A290138 0,1,4,8,22,53,184,353,1376,3977,363904,396498,39920896,40060127, %T A290138 1543910,4687418,1307674433536,1307902407753,355687428358144, %U A290138 355691118382364,162615882312376736,1267150213999727,51090942171713634304,51090956256672365547 %N A290138 Number of maximal subgroups of the symmetric group S_n. %C A290138 a(n) + 1, n > 1, is the number of maximal subsemigroups of each of the following monoids of degree n: the full transformation monoid, the symmetric inverse monoid, the dual symmetric inverse monoid, the uniform block bijection monoid, and the Brauer monoid. %C A290138 a(n) + 2 is the number of maximal subsemigroups of the partial transformation monoid of degree n. %C A290138 a(n) + 3, n > 1, is the number of maximal subsemigroups of the partial Brauer monoid of degree n. %C A290138 a(n) + 4, n > 1, is the number of maximal subsemigroups of the partition monoid of degree n. %H A290138 Wilf A. Wilson, <a href="/A290138/b290138.txt">Table of n, a(n) for n = 1..84</a> %H A290138 Utsithon Chaichompoo and Kritsada Sangkhanan, <a href="https://arxiv.org/abs/2411.15081">Transformation Semigroups Which Are Disjoint Union of Symmetric Groups</a>, arXiv:2411.15081 [math.RA], 2024. See p. 10. %H A290138 James East, Jitender Kumar, James D. Mitchell, and Wilf A. Wilson, <a href="https://arxiv.org/abs/1706.04967">Maximal subsemigroups of finite transformation and partition monoids</a>, arXiv:1706.04967 [math.GR], 2017. %o A290138 (GAP) Sum(List(ConjugacyClassesMaximalSubgroups(SymmetricGroup(n)), Size)); %Y A290138 Cf. A066115. %K A290138 nonn %O A290138 1,3 %A A290138 _James Mitchell_ and _Wilf A. Wilson_, Jul 21 2017