

A032444


a(1) = 1, a(2) = 16, a(n) = LCM(48, 2n^2) for n>2.


0



1, 16, 144, 96, 1200, 144, 2352, 384, 1296, 1200, 5808, 288, 8112, 2352, 3600, 1536, 13872, 1296, 17328, 2400, 7056, 5808, 25392, 1152, 30000, 8112, 11664, 4704, 40368, 3600, 46128, 6144, 17424, 13872, 58800, 2592, 65712, 17328, 24336, 9600
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OFFSET

1,2


COMMENTS

In the M. Reid reference the following is proved: Let S(n) be the set of all groups whose order is a product of primes congruent to 1 mod n. Then, a(n) = gcd{G  cc(G) : G in S(n)}, where cc(G) is the number of conjugacy classes of G.  Eric M. Schmidt, Apr 18 2013


REFERENCES

M. Reid, The number of conjugacy classes, Amer. Math. Monthly, 105 (1998), 359361.


LINKS

Table of n, a(n) for n=1..40.
Index to divisibility sequences
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).


FORMULA

a(n) = 3a(n12)  3a(n24) + a(n36) for n > 38.  Charles R Greathouse IV, Apr 18 2013


PROG

(MAGMA) [1, 16] cat [ LCM(48, 2*n^2) : n in [3..10] ];  from Sergei Haller (sergei(AT)sergeihaller.de), Dec 21 2006
(PARI) a(n)=if(n>3, lcm(48, 2*n^2), 15*n14) \\ Charles R Greathouse IV, Apr 18 2013


CROSSREFS

Sequence in context: A232311 A048533 A213349 * A017114 A092820 A060300
Adjacent sequences: A032441 A032442 A032443 * A032445 A032446 A032447


KEYWORD

nonn,easy


AUTHOR

N. J. A. Sloane.


EXTENSIONS

Definition rewritten by Eric M. Schmidt, Apr 18 2013


STATUS

approved



