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A359987
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Number of edge cuts in the n-ladder graph P_2 X P_n.
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3
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1, 11, 105, 919, 7713, 63351, 514321, 4148839, 33347041, 267489431, 2143168305, 17160184519, 137349160833, 1099102033911, 8794224638161, 70360221445159, 562911076526881, 4503422288363351, 36027988077717105, 288226686123491719, 2305826176955087553, 18446667292472959671
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OFFSET
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1,2
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LINKS
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Eric Weisstein's World of Mathematics, Edge Cut
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FORMULA
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a(n) = 13*a(n-1) - 42*a(n-2) + 16*a(n-3) for n > 3.
G.f.: x*(1 - 2*x + 4*x^2)/((1 - 8*x)*(1 - 5*x + 2*x^2)).
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PROG
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(PARI) Vec((1 - 2*x + 4*x^2)/((1 - 8*x)*(1 - 5*x + 2*x^2)) + O(x^25))
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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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STATUS
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approved
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