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%I #6 Nov 06 2019 17:50:59
%S 0,1,2,6,8,10,36,14,64,72,180,22,720,26,924,600,2048,34,10800,38,
%T 12240,2856,22572,46,144000
%N Number of subsets of the n-th roots of 1 with absolute value of sum = 1.
%C a(n) is divisible by n (rotation symmetry). a(n)/n differs from A107754 by a factor of 2 for odd n.
%t <<DiscreteMath`Combinatorica`; Table[Plus @@ Count[KSubsets[Range[n], k], q_List/;Chop[ -1+Abs[Plus @@ (E^((2.*Pi*I*q)/n))]] === 0], {n, 16}, {k, 0, n}]
%Y Row sums of A108416.
%Y Cf. A107754, A103314.
%K nonn,more
%O 0,3
%A _Wouter Meeussen_, Jun 02 2005
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