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A081685
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A sum of decreasing powers.
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2
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1, 0, -2, 24, 382, 3480, 26398, 183624, 1217662, 7844280, 49595998, 309603624, 1915345342, 11771312280, 71987479198, 438579414024, 2664184199422, 16146411375480, 97676153291998, 590010215086824, 3559688013155902, 21455704981601880, 129219894496730398
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OFFSET
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0,3
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COMMENTS
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LINKS
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FORMULA
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a(n)=6^n-5^n-4^n-3^n+3*2^n
G.f.:(-1-636*x^4+516*x^3-153*x^2+20*x)/((6*x-1)*(4*x-1)*(3*x-1)*(2*x-1)*(5*x-1)) [From Maksym Voznyy (voznyy(AT)mail.ru), Jul 27 2009]
a(0)=1, a(1)=0, a(2)=-2, a(3)=24, a(4)=382, a(n)=20*a(n-1)- 155*a(n-2)+ 580*a(n-3)-1044*a(n-4)+720*a(n-5). - Harvey P. Dale, Sep 15 2014
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MATHEMATICA
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Table[6^n-5^n-4^n-3^n+3*2^n, {n, 0, 30}] (* or *) LinearRecurrence[{20, -155, 580, -1044, 720}, {1, 0, -2, 24, 382}, 30] (* Harvey P. Dale, Sep 15 2014 *)
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CROSSREFS
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KEYWORD
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easy,sign
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AUTHOR
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STATUS
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approved
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