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%I #22 Jan 20 2018 16:15:09
%S 36,4150,699252,134223976,27487816992,5864063066500,1286742755471400,
%T 288230376353050816,65588423374144427520,15111572745224096425720,
%U 3516875111606393874082104,825293359523595646117352176,195023169265881489687952047216
%N Number of distinct n X 8 toroidal binary arrays.
%H Vaclav Kotesovec, <a href="/A184270/b184270.txt">Table of n, a(n) for n = 1..410</a>
%H S. N. Ethier, <a href="http://arxiv.org/abs/1301.2352">Counting toroidal binary arrays</a>, arXiv preprint arXiv:1301.2352, 2013 and <a href="https://cs.uwaterloo.ca/journals/JIS/VOL16/Ethier/ethier2.html">J. Int. Seq. 16 (2013) #13.4.7</a>.
%F a(n) ~ 2^(8*n-3) / n. - _Vaclav Kotesovec_, Sep 04 2014
%p with(numtheory):
%p a:= n-> add(add(phi(c)*phi(d) *2^(8*n/ilcm(c, d)),
%p d=divisors(n)), c=[1,2,4,8])/(8*n):
%p seq(a(n), n=1..20); # _Alois P. Heinz_, Aug 25 2012
%Y Column 8 of A184271.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 10 2011
%E More terms from _Alois P. Heinz_, Aug 25 2012
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