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%I #16 Oct 31 2017 20:57:42
%S 24,700,29184,1398500,71582944,3817765120,209430787824,11728124734500,
%T 667199944873344,38430716856090160,2235968978631715024,
%U 131176846748291651840,7749524484709164817824,460543169377106318541400,27509778650786228522002432
%N Number of distinct n X 3 toroidal 0..3 arrays.
%H Andrew Howroyd, <a href="/A184274/b184274.txt">Table of n, a(n) for n = 1..100</a>
%t T[n_, k_] := (1/(n*k))*Sum[Sum[EulerPhi[c]*EulerPhi[d]*4^(n*k/LCM[c, d]), {d, Divisors[k]}], {c, Divisors[n]}]; a[n_] := T[n, 3]; Array[a, 15] (* _Jean-François Alcover_, Oct 31 2017, after _Andrew Howroyd_ *)
%Y Column 3 of A184277.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 10 2011
%E Terms a(9) and beyond from _Andrew Howroyd_, Sep 27 2017
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