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A081687 A sum of decreasing powers. 2
1, 2, 2, 20, 542, 8132, 94502, 964700, 9138782, 82619732, 724180502, 6213565580, 52507598222, 438786732932, 3636161064902, 29939329241660, 245281233244862, 2001531240407732, 16280816416067702, 132088684297864940 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Binomial transform of A081686

LINKS

Table of n, a(n) for n=0..19.

Index entries for linear recurrences with constant coefficients, signature (30,-355,2070,-5944,6720).

FORMULA

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]

CROSSREFS

Cf. A081890.

Sequence in context: A002907 A184717 A134046 * A082811 A014353 A153438

Adjacent sequences:  A081684 A081685 A081686 * A081688 A081689 A081690

KEYWORD

easy,nonn

AUTHOR

Paul Barry, Mar 30 2003

EXTENSIONS

Signature corrected by Colin Barker, Sep 07 2012

STATUS

approved

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Last modified March 2 08:35 EST 2021. Contains 341745 sequences. (Running on oeis4.)