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A003110
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a(n) = number of special odd permutations of 2*n+1.
(Formerly M0393)
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4
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0, 2, 2, 108, 2028, 32870, 1213110, 46493784, 2310521000, 137466038346, 9842687925450, 832295357128500
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OFFSET
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1,2
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COMMENTS
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a(n) is the number of odd permutations, pi(0),...,pi(2*n), of 0,...,2*n such that pi(0) = 0 and p(k) = k + pi(k) (mod 2*n+1), k=0,...,2*n is also a permutation of 0,...,2*n. - Sean A. Irvine, Jan 31 2015
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REFERENCES
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N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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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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EXTENSIONS
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STATUS
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approved
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