

A073043


Number of nonisomorphic (finite) groups with n conjugacy classes.


5



1, 1, 2, 4, 8, 8, 12, 21, 26, 38, 35, 32
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OFFSET

1,3


REFERENCES

E. K. Annavaddar, Determination of the Finite Groups Having Eight Conjugacy Classes. Ph.D. Diss., Arizona State Univ., 1971.
I. M. Isaacs, Algebra, Brooks/Cole, 1994; pp. 4849 (for n = 4).
T. Y. Lam, Exercises in Classical Ring Theory, Springer, 1995; pp. 9293 (for n=1,2,3).


LINKS

Table of n, a(n) for n=1..12.
J. Poland, Finite groups with a given number of conjugate classes<, Canad. J. Math. 20 1968 456464 (for n <= 7).
J. Sondow and K. MacMillan, Primary pseudoperfect numbers, arithmetic progressions, and the ErdosMoser equation, Amer. Math. Monthly, 124 (2017) 232240 (see page 232); arXiv:math/1812.06566 [math.NT], 2018.
Antonio Vera Lopez and Juan Vera Lopez, Classification of finite groups according to the number of conjugacy classes, Israel Journal of Mathematics, 51 (1985), No. 4.
Index entries for sequences related to groups


FORMULA

Equals A003061 + A000688.


EXAMPLE

n=1: C_1; n=2: C_2; n=3: A_3 or S_3; n=4: C_2 X C_2, C_4, A_4, D_10.


CROSSREFS

Cf. A109230, A003061, A002319, A006379, A000688.
Sequence in context: A260514 A123263 A008218 * A083542 A181533 A263981
Adjacent sequences: A073040 A073041 A073042 * A073044 A073045 A073046


KEYWORD

nonn,nice,more,hard


AUTHOR

N. J. A. Sloane, Aug 30, 2002


EXTENSIONS

Corrected and extended by A. S. Muktibodh (amukti2000(AT)yahoo.com), Nov 07 2006


STATUS

approved



