%I M1728 #26 Jan 31 2022 01:13:21
%S 0,0,1,2,7,7,11,18,24,37,34,30
%N Number of non-Abelian (finite) groups with n conjugacy classes.
%D E. K. Annavaddar, Determination of the Finite Groups Having Eight Conjugacy Classes. Ph.D. Diss., Arizona State Univ., 1971.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H J. Poland, <a href="http://dx.doi.org/10.4153/CJM-1968-042-9">Finite groups with a given number of conjugate classes<</a>, Canad. J. Math. 20 1968 456-464.
%H J. Poland, <a href="/A002319/a002319_1.pdf">Finite groups with a given number of conjugate classes</a>, Canad. J. Math. 20 1968 456-464. (Annotated scanned copy)
%H <a href="/index/Gre#groups">Index entries for sequences related to groups</a>
%F A073043(n) = a(n) + A000688(n).
%e 1,1,2,4,8,8,12,21,26,38,35,32 (A073043)
%e 1,1,1,2,1,1,.1,.3,.2,.1,.1,.2 (subtract A000688)
%e -----------------------------
%e 0,0,1,2,7,7,11,18,24,37,34,30 (A003061)
%Y Cf. A002319, A000688, A073043 (for total number), A006379.
%K nonn,nice,more,hard
%O 1,4
%A _N. J. A. Sloane_
%E a(8) corrected and a(9)-a(12) from _Michael Somos_, Aug 10 2010