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A179063
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Number of non-attacking placements of 8 rooks on an n X n board.
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4
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0, 0, 0, 0, 0, 0, 0, 40320, 3265920, 81648000, 1097712000, 9879408000, 66784798080, 363606122880, 1669619952000, 6678479808000, 23828156352000, 77203226580480, 230333593351680, 639815537088000, 1669577821632000, 4122835028928000
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OFFSET
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1,8
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LINKS
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Index entries for linear recurrences with constant coefficients, signature (17, -136, 680, -2380, 6188, -12376, 19448, -24310, 24310, -19448, 12376, -6188, 2380, -680, 136, -17, 1).
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FORMULA
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a(n) = 8!*binomial(n,8)^2.
G.f.: -40320*x^8*(x^8 +64*x^7 +784*x^6 +3136*x^5 +4900*x^4 +3136*x^3 +784*x^2 +64*x +1) / (x -1)^17. - Colin Barker, Jan 08 2013
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PROG
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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