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A317981
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Expansion of x*(125 + 8028*x + 42237*x^2 + 42272*x^3 + 8007*x^4 + 132*x^5 - x^6) / (1 - x)^8.
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5
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125, 9028, 110961, 684176, 2871325, 9402660, 25872833, 62572096, 136972701, 276971300, 524988145, 943023888, 1618774781, 2672907076, 4267591425, 6616398080, 9995653693, 14757360516, 21343778801, 30303773200, 42311023965, 58184203748, 78909220801
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OFFSET
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1,1
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COMMENTS
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Seems to be the negative of the first column of A316387.
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LINKS
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FORMULA
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G.f.: x*(125 + 8028*x + 42237*x^2 + 42272*x^3 + 8007*x^4 + 132*x^5 - x^6) / (1 - x)^8.
a(n) = 20*n^7 + 70*n^6 + 70*n^5 - 28*n^3 - 7*n^2.
a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8) for n>8.
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PROG
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(PARI) Vec(x*(125 + 8028*x + 42237*x^2 + 42272*x^3 + 8007*x^4 + 132*x^5 - x^6) / (1 - x)^8 + O(x^40))
(PARI) a(n) = 20*n^7 + 70*n^6 + 70*n^5 - 28*n^3 - 7*n^2
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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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