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 A282673 The number of groups of order n that are not Lagrangian. 0
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 OFFSET 1,36 COMMENTS A group of order n is Lagrangian if it has a subgroup of order d for each divisor d of n. LINKS Mathematics StackExchange Discussion, Complete classification of the groups for which converse of Lagrange's Theorem holds PROG (GAP) a:=function(n) local i, N, G, m; N:=NumberSmallGroups(n); m:=0; for i in [1..N] do G:=SmallGroup(n, i); if Set(List(ConjugacyClassesSubgroups( G ), t->Size(Representative(t)))<>DivisorsInt(n) then m:=m+1; fi; od; return m; end;; CROSSREFS Sequence in context: A181000 A061853 A010104 * A327159 A280051 A030121 Adjacent sequences:  A282670 A282671 A282672 * A282674 A282675 A282676 KEYWORD nonn AUTHOR W. Edwin Clark, Feb 20 2017 STATUS approved

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Last modified October 18 12:18 EDT 2019. Contains 328160 sequences. (Running on oeis4.)