A184268 Number of distinct n X 6 toroidal binary arrays.

14, 362, 14624, 699600, 35792568, 1908897152, 104715443852, 5864063066500, 333599974922264, 19215358463836552, 1117984489446008100, 65588423376054708480, 3874762242361630560584, 230271584688657874664612, 13754889325393505198471808, 825293359523595646115953700

Offset

1,1

Links

Vaclav Kotesovec, Table of n, a(n) for n = 1..550

S. N. Ethier, Counting toroidal binary arrays, arXiv preprint arXiv:1301.2352, 2013 and J. Int. Seq. 16 (2013) #13.4.7 .

Formula

a(n) ~ 64^n / (6*n). - Vaclav Kotesovec, Sep 04 2014

Maple

with(numtheory):
a:= n-> add(add(phi(c)*phi(d) *2^(6*n/ilcm(c, d)),
        d=divisors(n)), c=[1, 2, 3, 6])/(6*n):
seq(a(n), n=1..25);  # Alois P. Heinz, Aug 25 2012

Crossrefs

Column 6 of A184271.

Sequence in context: A253457 A239784 A113673 * A223383 A215300 A159535

Adjacent sequences: A184265 A184266 A184267 * A184269 A184270 A184271

Keyword

nonn

Author

R. H. Hardin, Jan 10 2011

Extensions

More terms from Alois P. Heinz, Aug 25 2012

Status

approved