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A099132
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Quintisection of 1/(1-x^5-x^6).
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4
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1, 1, 1, 1, 1, 1, 2, 7, 22, 57, 127, 253, 464, 804, 1354, 2289, 4005, 7372, 14198, 28033, 55523, 108699, 208982, 394555, 734561, 1357136, 2504932, 4643816, 8671852, 16313856, 30855957, 58502733, 110882143, 209689343, 395358538, 743376838
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OFFSET
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0,7
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LINKS
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FORMULA
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G.f.: (1-x)^4/((1-x)^5-x^6);
a(n) = Sum_{k=0..n} binomial(k, 5(n-k));
a(n) = 5a(n-1)-10a(n-2)+10a(n-3)-5a(n-4)+a(n-5)+a(n-6);
a(n) = Sum_{k=0..floor(n/5)} binomial(n-k, 5k). - Paul Barry, May 09 2005
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MATHEMATICA
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LinearRecurrence[{5, -10, 10, -5, 1, 1}, {1, 1, 1, 1, 1, 1}, 40] (* Harvey P. Dale, Aug 20 2012 *)
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PROG
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(PARI) Vec((1-x)^4/((1-x)^5-x^6) + O(x^40)) \\ Michel Marcus, Sep 06 2017
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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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