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A064941
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Quartering a 2n X 2n chessboard (reference A257952) considering only the 90-deg rotationally symmetric results (omitting results with only 180-deg symmetry).
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5
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1, 3, 26, 596, 38171, 7083827, 3852835452, 6200587517574, 29752897658253125, 427721252609771505989, 18479976131829456895423324, 2405174963192312814001570260392, 944597040906414962273553855513194341, 1120924326970482645724785944664901286951323
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OFFSET
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1,2
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LINKS
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FORMULA
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No formula known. However, the subset of solutions consisting of "tiles" with minimum edge lengths from a corner of the board to the center is A001700.
This sequence can be computed by counting paths in a graph. To compute the n-th term a graph with n X (n-1) vertices is required. Each graph vertex corresponds to 4 intersections between grid lines on the chessboard and graph edges correspond to ways of cutting the board along the grid lines. Frontier (matrix-transfer) graph path counting methods can then be applied to the graph to get the actual count. - Andrew Howroyd, Apr 18 2016
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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Walter Gilbert (Walter(AT)Gilbert.net), Oct 28 2001
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EXTENSIONS
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STATUS
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approved
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