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A154655
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Number of permutations of length n within distance 6.
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5
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1, 1, 2, 6, 24, 120, 720, 5040, 30960, 172200, 899064, 4553166, 22934774, 116914351, 610093513, 3222826972, 17101449940, 90706002192, 479654768640, 2527274267136, 13280313508416, 69734129749632, 366283822765632, 1925290900630896, 10126754515065868
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OFFSET
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0,3
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COMMENTS
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a(n) equals the permanent of the n X n matrix with 1's along the central thirteen diagonals, and 0's everywhere else. - John M. Campbell, Jul 10 2011
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LINKS
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FORMULA
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G.f. is a rational function f(x)/g(x) where f has degree 482 and g has degree 494.
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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