%I #8 Mar 30 2012 16:49:24

%S 1,1,3,1,9,1,15,7,33,1,99,1,129,37,255,1,999,1,1155,133,2049,1,9999,

%T 31,8193,511,16899,1,146853,1,65535,2053,131073,157,999999,1,524289,

%U 8197,1336335,1,11680389,1,4202499,54871,8388609,1,99999999,127,45435423,131077

%N Number of nonempty subsets of the set of vertices of a regular n-gon in the plane such that their center of gravity is the center of the polygon.

%Y This is A103314(n) - 1: see that entry for much more information.

%K nonn

%O 2,3

%A Sharon Sela (sharonsela(AT)hotmail.com), May 24 2002

%E Edited by _N. J. A. Sloane_ Jan 19 2008 at the suggestion of Max Alekseyev and M. F. Hasler.