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A081687
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A sum of decreasing powers.
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2
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1, 2, 2, 20, 542, 8132, 94502, 964700, 9138782, 82619732, 724180502, 6213565580, 52507598222, 438786732932, 3636161064902, 29939329241660, 245281233244862, 2001531240407732, 16280816416067702, 132088684297864940
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OFFSET
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0,2
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COMMENTS
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Binomial transform of A081686
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LINKS
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Table of n, a(n) for n=0..19.
Index entries for linear recurrences with constant coefficients, signature (30,-355,2070,-5944,6720).
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FORMULA
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a(n)=8^n-7^n-6^n-5^n+3*4^n.
G.f. -(2456*x^4-1400*x^3+297*x^2-28*x+1)/((4*x-1)*(5*x-1)*(6*x-1)*(7*x-1)*(8*x-1)). [Colin Barker, Aug 12 2012]
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CROSSREFS
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Cf. A081890.
Sequence in context: A002907 A184717 A134046 * A082811 A014353 A153438
Adjacent sequences: A081684 A081685 A081686 * A081688 A081689 A081690
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KEYWORD
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easy,nonn
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AUTHOR
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Paul Barry, Mar 30 2003
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EXTENSIONS
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Signature corrected by Colin Barker, Sep 07 2012
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STATUS
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approved
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