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Let G_n be the group of invertible 2 X 2 matrices mod n (sequence A000252). a(n) is the maximal degree of an irreducible representation of G_n.
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%I #5 May 23 2013 14:43:07

%S 1,2,4,6,6,8,8,12,12,12,12,24,14,16,24,24,18,24,20,36,32,24,24,48

%N Let G_n be the group of invertible 2 X 2 matrices mod n (sequence A000252). a(n) is the maximal degree of an irreducible representation of G_n.

%C a(n) is multiplicative and for an odd prime p : a(p) = p + 1 . The number of irreducible representations of G_n is in sequence A062354.

%C Conjecture: a(2n) = 2*A001615(n). - _Ralf Stephan_, Mar 26 2004

%Y A000252, A062354

%K nonn

%O 1,2

%A Dan Fux (dan.fux(AT)OpenGaia.com or danfux(AT)OpenGaia.com), Nov 29 2001