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%I #4 Mar 30 2012 16:50:30
%S 0,1,0,6,30,246,1670,11132,71292,442642,2685392,15995460,93918296,
%T 545202570,3136082636,17904903342,101594620516,573479526968,
%U 3222969297490,18045116141404,100704940182826,560417613651508
%N Series expansion for first area weighted moment of neighbor-avoiding polygons on square lattice.
%H I. Jensen, <a href="/A121772/b121772.txt">Table of n, a(n) for n = 1..41</a> (from link below)
%H I. Jensen, <a href="http://www.ms.unimelb.edu.au/~iwan/polygons/Polygons_ser.html">More terms</a>
%K nonn
%O 1,4
%A _N. J. A. Sloane_, Aug 30 2006