%I A107754
%S A107754 1,1,1,2,1,6,1,8,4,18,1,60,1,66,20,128,1,600,1,612,68,1026,1,6000,16,
%T A107754 4098,256,8580,1,95226,1,32768
%N A107754 Number of subsets of the n-th roots of unity that sum to 1.
%F A107754 For prime p, a(p^i)=2^(p^(i-1)-1).
%t A107754 << DiscreteMath`Combinatorica`; f[n_] := Plus @@ Table[ Count[ KSubsets[ 
               Range[n], k], q_List /; Chop[ -1 + Plus @@ (E^((2.*Pi*I*q)/n))] === 
               0], {k, 0, n}]; Table[ f[n], {n, 24}] (from Robert G. Wilson v (rgwv(AT)rgwv.com), 
               Jun 03 2005)
%Y A107754 Cf. A103314 (number of subsets of the n-th roots of unity summing to 
               zero) and A108417 (number of subsets of the n-th roots of unity summing 
               to the absolute value of 1.
%Y A107754 Sequence in context: A050932 A166120 A007956 this_sequence A139625 A053785 
               A060173
%Y A107754 Adjacent sequences: A107751 A107752 A107753 this_sequence A107755 A107756 
               A107757
%K A107754 nonn
%O A107754 1,4
%A A107754 T. D. Noe (noe(AT)sspectra.com), May 23 2005