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A131932 Number of nonisomorphic nonsolvable groups of order A056866(n). 4
1, 3, 1, 1, 8, 1, 3, 6, 1, 26, 2, 2, 5, 2, 8, 23, 1, 6, 1, 107, 6, 1, 14, 1, 1, 1, 19, 2, 8, 28, 1, 93, 2, 4, 5, 5, 22, 1, 10, 1, 1, 588, 2, 20, 5, 1, 64, 4, 1, 5, 2, 5, 81, 1, 1, 18, 1, 25, 112, 2, 5, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
REFERENCES
O. L. Hoelder, Bildung zusammengesetzter Gruppen, Math. Ann., 46 (1895), 321-422; see p. 420.
LINKS
EXAMPLE
a(1) = 1 because there is only 1 nonisomorphic and nonsolvable group of order 60: A_5 (alternating group of 5th degree).
a(2) = 3 because there are 3 different nonisomorphic and nonsolvable groups of order 120.
PROG
(GAP) NrUnsolvable := function(n) local i, count; count := 0; for i in [1..NumberSmallGroups(n)] do if not IsSolvableGroup(SmallGroup(n, i)) then count := count + 1; fi; od; return count; end; # Eric M. Schmidt, Apr 04 2013
(GAP) LoadPackage("GrpConst"); NrUnsolvable := function(n) local i, j, num; num := 0; for i in DivisorsInt(n) do if i<>1 then for j in [1..NrPerfectGroups(i)] do num := num + Length(Remove(UpwardsExtensions(PerfectGroup(IsPermGroup, i, j), n/i))); od; fi; od; return num; end; # Eric M. Schmidt, Nov 14 2013
CROSSREFS
Sequence in context: A297191 A147990 A134567 * A016462 A348693 A198618
KEYWORD
nonn
AUTHOR
Artur Jasinski, Jul 30 2007, Oct 20 2007
EXTENSIONS
Edited by N. J. A. Sloane, Oct 08 2007
More terms from Eric M. Schmidt, Apr 04 2013
a(44)-a(63) from Eric M. Schmidt, Nov 14 2013
STATUS
approved

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Last modified April 20 12:36 EDT 2024. Contains 371844 sequences. (Running on oeis4.)