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A335694
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a(n) = 3*binomial(n,4) - 6*binomial(n,3) + 4*binomial(n,2) - 2.
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0
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-2, -2, 2, 4, 1, -7, -17, -23, -16, 16, 88, 218, 427, 739, 1181, 1783, 2578, 3602, 4894, 6496, 8453, 10813, 13627, 16949, 20836, 25348, 30548, 36502, 43279, 50951, 59593, 69283, 80102, 92134, 105466, 120188, 136393, 154177, 173639, 194881, 218008, 243128, 270352, 299794, 331571, 365803, 402613, 442127, 484474, 529786
(list;
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listen;
history;
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OFFSET
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0,1
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REFERENCES
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I. Kaplansky and J. Riordan, The problème des ménages, Scripta Math. 12, (1946), 113-124. See p. 123.
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LINKS
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FORMULA
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a(n) = (n^4 - 14*n^3 + 51*n^2 - 38*n - 16)/8.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n > 4.
G.f.: (-11*x^4 + 6*x^3 + 8*x^2 - 8*x + 2)/(x - 1)^5. (End)
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PROG
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CROSSREFS
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KEYWORD
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sign,easy
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AUTHOR
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STATUS
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approved
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