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A319326
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a(n) is the number of column convex polyglasses (polyiamonds which need only touch at corners) with n cells.
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2
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2, 12, 84, 612, 4532, 33762, 252106, 1884120, 14084674, 105295512, 787178752
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OFFSET
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1,1
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COMMENTS
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A polyglass is column convex if the intersection of its interior with any vertical line through the centers of the cells is connected.
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LINKS
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EXAMPLE
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There are four triglasses that are not column convex. So a(2) = A319324(3) - 4 = 84.
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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