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Minimal number of conjugacy classes (which is also the number of irreducible representations) in G where G is a finite group of order n.
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%I #6 Aug 30 2012 03:04:13

%S 1,2,3,4,5,3,7,5,9,4,11,4,13,5,15,7,17,6,19,5,5,7,23,5,25,8,11,10,29,

%T 9,31,11,33,10,35,6,37,11,7,10,41,7,43,14,45,13,47,8,49,14,51,7,53,10,

%U 7,8,9,16,59,5,61,17,15,13,65,18,67,8,69,19,71,6,73

%N Minimal number of conjugacy classes (which is also the number of irreducible representations) in G where G is a finite group of order n.

%C a(n) <= n with equality iff n belongs to sequence A051532.

%H Eric M. Schmidt, <a href="/A060653/b060653.txt">Table of n, a(n) for n = 1..1023</a>

%e a(6) = 3 because there are two groups of order 6, the cyclic group with 6 classes and S_3 with 3 classes.

%o (GAP) A060653 := function(n) local min, i; min := n; for i in [1..NumberSmallGroups(n)] do min := Minimum(min, NrConjugacyClasses(SmallGroup(n,i))); od; return min; end; # _Eric M. Schmidt_, Aug 30 2012

%Y A051532.

%K nonn

%O 1,2

%A Noam Katz (noamkj(AT)hotmail.com), Apr 17 2001

%E More terms from _Eric M. Schmidt_, Aug 30 2012