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A093118 Triangle T read by rows: T(m,n) = number of convex polyominoes with an m+1 x n+1 minimal bounding rectangle, m>0, n<=m. 2
5, 13, 68, 25, 222, 1110, 41, 555, 3951, 19010, 61, 1171, 11263, 70438, 329126, 85, 2198, 27468, 216618, 1245986, 5693968, 113, 3788, 59676, 579330, 4022546, 21832492, 98074332, 145, 6117, 118605, 1389927, 11462495, 72887139 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

V. J. W. Guo and J. Zeng, The number of convex polyominoes and the generating function of Jacobi polynomials.

Ira Gessel, On the number of convex polyominoes.

FORMULA

T(m, n) = (m+n+mn)/(m+n)*C(2m+2n, 2m) - 2mn/(m+n)*C(m+n, m)^2.

CROSSREFS

Columns T(m, 1) = A001844(m), T(m, 2) = A093119(m). Diagonal T(n, n) = A093120(n).

Sequence in context: A018678 A149575 A156101 * A087506 A068487 A075063

Adjacent sequences:  A093115 A093116 A093117 * A093119 A093120 A093121

KEYWORD

nonn,tabl

AUTHOR

Ralf Stephan, Mar 21 2004

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Last modified February 17 23:45 EST 2012. Contains 206085 sequences.