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%I #26 Dec 27 2016 14:30:28
%S 1,67,212,1983,1120,14204,3652,43339,24033,75040,19156,420396,35872,
%T 244684,237440,821335,99472,1610211,152404,2220960,774224,1283452,
%U 318532,9187868,810969,2403424,2222704,7241916,783904,15908480,1016836,14445411,4061072,6664624,4090240,47657439,2031712
%N Number of subgroups of the group C_n x C_n x C_n x C_n, where C_n is the cyclic group of order n.
%H Charles R Greathouse IV, <a href="/A280162/b280162.txt">Table of n, a(n) for n = 1..10000</a>
%H Max Alekseyev, <a href="http://home.gwu.edu/~maxal/gpscripts/">PARI/GP Scripts for Miscellaneous Math Problems</a>
%H G. A. Miller, <a href="http://www.jstor.org/stable/2007151">On the subgroups of an abelian group</a>, The Annals of Mathematics, 2nd Ser. 6:1 (1904), pp. 1-6.
%H L. Toth, <a href="https://arxiv.org/abs/1611.03302">The number of subgroups of the group Z_m x Z_n x Z_r x Z_s</a>, arXiv:1611.03302 [math.GR], (2016).
%o (PARI) \\ For numsubgrp, see the Alekseyev link.
%o a(n)=my(f=factor(n)); prod(i=1,#f~, numsubgrp(f[i,1],f[i,2]*[1,1,1,1])) \\ _Charles R Greathouse IV_, Dec 27 2016
%Y Cf. A060724, A064803.
%K nonn,mult
%O 1,2
%A _Laszlo Toth_, Dec 27 2016
%E Terms a(32) and beyond from _Charles R Greathouse IV_, Dec 27 2016