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 A218915 Number of missing subgroup orders of the symmetric group, that is, i divides Factorial(n) but the symmetric group on n points does not have a subgroup of order i. 0
 0, 0, 0, 0, 0, 3, 9, 29, 47, 86, 157, 401, 576, 1316 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 LINKS L. Naughton and G. Pfeiffer, Integer sequences realized by the subgroup pattern of the symmetric group, arXiv:1211.1911 [math.GR], 2012-2013. Liam Naughton, CountingSubgroups.g Liam Naughton and Goetz Pfeiffer, Tomlib, The GAP table of marks library FORMULA a(n) = A027423(n) - A218913(n). MATHEMATICA A[s_Integer] := With[{s6 = StringPadLeft[ToString[s], 6, "0"]}, Cases[ Import["https://oeis.org/A" <> s6 <> "/b" <> s6 <> ".txt", "Table"], {_, _}][[All, 2]]]; A027423 = A@027423; A218913 = A@218913; a[n_] := A027423[[n+1]] - A218913[[n+1]]; a /@ Range[0, 13] (* Jean-François Alcover, Jan 08 2020 *) PROG (GAP) Size(Difference(DivisorsInt(Factorial(n)), DuplicateFreeList(List(ConjugacyClassesSubgroups(SymmetricGroup(n)), x->Size(Representative(x)))))); CROSSREFS Sequence in context: A148937 A047137 A058145 * A258064 A161590 A192245 Adjacent sequences:  A218912 A218913 A218914 * A218916 A218917 A218918 KEYWORD nonn,more AUTHOR Liam Naughton, Nov 09 2012 STATUS approved

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Last modified April 7 15:56 EDT 2020. Contains 333306 sequences. (Running on oeis4.)