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A064803 Number of subgroups of the group C_n X C_n X C_n (where C_n is the cyclic group of order n). 4
1, 16, 28, 129, 64, 448, 116, 802, 445, 1024, 268, 3612, 368, 1856, 1792, 4387, 616, 7120, 764, 8256, 3248, 4288, 1108, 22456, 2607, 5888, 5776, 14964, 1744, 28672, 1988, 22308, 7504, 9856, 7424, 57405, 2816, 12224, 10304, 51328, 3448, 51968, 3788, 34572, 28480, 17728, 4516, 122836, 9009, 41712 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

For a prime p: a(p) = 2*(p^2+p+2). - Vladeta Jovovic, Oct 22 2001

LINKS

Table of n, a(n) for n=1..50.

Mario Hampejs and László Tóth, On the subgroups of finite Abelian groups of rank three, Annales Univ. Sci. Budapest., Sect. Comp. 39 (2013) 111-124.

MAPLE

A064803 := proc(n)

    local a, f, nu, p, j ;

    a := 1 ;

    for f in ifactors(n)[2] do

        nu := op(2, f) ;

        p := op(1, f) ;

        add( (nu-floor((j-1)/2))*(2*j-floor((j-1)/2))*p^(2*nu-j), j=0..2*nu) ;

        a := a*% ;

    end do:

    a ;

end proc: # R. J. Mathar, May 11 2013

CROSSREFS

Cf. A060648, A060724.

Sequence in context: A211570 A184031 A206259 * A220762 A246345 A054314

Adjacent sequences:  A064800 A064801 A064802 * A064804 A064805 A064806

KEYWORD

nonn,mult

AUTHOR

Dan Fux (dan.fux(AT)OpenGaia.com or danfux(AT)OpenGaia.com), Oct 21 2001

EXTENSIONS

More terms from Laszlo Toth, May 11 2013

STATUS

approved

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Last modified October 15 05:43 EDT 2019. Contains 328026 sequences. (Running on oeis4.)