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%I #2 Mar 30 2012 18:49:09
%S 0,0,1,0,1,0,1,0,3,0,4,1,11,1,23,4,62,11,150,38,411,118,1081,389
%N a(n) is the number of triangular polyominoes (polyiamonds) with n edges.
%C An n-celled polyiamond with perimeter p has (3n+p)/2 edges. The maximum number of edges in an n-celled polyiamond is 2n+1.
%H Isoperimetrical Polyiamonds at <a href="http://www.recmath.com/PolyPages/">Poly Pages</a>
%Y Cf. A000577: Triangular polyominoes (or polyiamonds) with n cells. A057729: Number of triangular polyominoes (or polyiamonds) [A000577] with perimeter n. A131481: a(n) is the number of n-cell polyiamonds (triangular polyominoes) with perimeter n+2.
%K hard,more,nonn
%O 1,9
%A _Tanya Khovanova_, Jul 28 2007