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A081686 A sum of decreasing powers. 1
1, 1, -1, 19, 467, 5611, 53459, 455659, 3648707, 28119691, 211372019, 1562038699, 11405181347, 82545287371, 593501306579, 4245828252139, 30255066944387, 214924122640651, 1522971386761139, 10770190567911979, 76039651374633827, 536127709619251531 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Binomial transform of A081685

LINKS

Table of n, a(n) for n=0..21.

Index entries for linear recurrences with constant coefficients, signature (25,-245,1175,-2754,2520).

FORMULA

a(n)=7^n-6^n-5^n-4^n+3*3^n.

G.f.: -(1326*x^4-886*x^3+219*x^2-24*x+1)/((3*x-1)*(4*x-1)*(5*x-1)*(6*x-1)*(7*x-1)). [Colin Barker, Sep 07 2012]

CROSSREFS

Cf. A081687.

Sequence in context: A285398 A201798 A284197 * A284163 A218477 A003700

Adjacent sequences:  A081683 A081684 A081685 * A081687 A081688 A081689

KEYWORD

easy,sign

AUTHOR

Paul Barry, Mar 30 2003

STATUS

approved

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Last modified June 12 09:24 EDT 2021. Contains 344946 sequences. (Running on oeis4.)