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A259333
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Triangle read by rows: T(n,k) = number of column-convex polyominoes with bond-perimeter 2*n+2 and k columns (1 <= k <= n).
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1
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1, 1, 1, 1, 4, 1, 1, 9, 9, 1, 1, 16, 37, 16, 1, 1, 25, 105, 106, 25, 1, 1, 36, 240, 446, 245, 36, 1
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OFFSET
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1,5
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LINKS
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FORMULA
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There is an explicit formula for T(n,k) - see Delest (1987), Theorem 24.
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EXAMPLE
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Triangle begins:
1,
1,1,
1,4,1,
1,9,9,1,
1,16,37,16,1,
1,25,105,106,25,1,
1,36,240,446,245,36,1,
...
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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