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A243221
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Number of quarter-square matchings of the n X n grid graph.
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2
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1, 1, 4, 44, 2593, 407620, 333518324, 696849783788, 7561681603209033, 204785162442300693673, 28874426647917459828127044, 10023323177854055068860282476760, 18172145684566998309243670369029131178, 80387219406473992671391703779030095453926416
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OFFSET
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0,3
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COMMENTS
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Number of ways floor(n^2/4) dominoes can be placed on an n X n chessboard. a(n) is the central term in the n-th row of A242861.
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LINKS
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FORMULA
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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