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%I #1 Jan 24 2006 03:00:00
%S 1,2,3,6,9,24
%N Erroneous enumeration of "congruent and symmetric divisions" of n points on a circle.
%D Motzkin, T. "Relations Between Hypersurface Cross Ratios and a Combinatorial Formula for Partitions of a Polygon for Permanent Preponderance and for Non-Associative Products." Bull. Amer. Math. Soc. 54, page 360, 1948.
%H L. Smiley, <a href="http://www.math.uaa.alaska.edu/~smiley/nc/10NC.pdf">a(5)</a>
%Y See A111275 for the correct enumeration.
%K dead
%O 1,2
%E a(5)=9 is clearly a clerical error.