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A027658 C(n+2,2)+C(n+4,5). 2
1, 4, 12, 31, 71, 147, 280, 498, 837, 1342, 2068, 3081, 4459, 6293, 8688, 11764, 15657, 20520, 26524, 33859, 42735, 53383, 66056, 81030, 98605, 119106, 142884, 170317, 201811, 237801, 278752 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (6,-15,20,-15,6,-1).

FORMULA

G.f.: -(x^3-3*x^2+2*x-1) / (x-1)^6. - Colin Barker, Apr 15 2013

a(n) = A000217(n+1) + A000389(n+4) = (n+1)*(n+2)*(60+12*n+7*n^2+n^3)/120. - R. J. Mathar, Sep 29 2020

MATHEMATICA

CoefficientList[Series[-(x^3 - 3 x^2 + 2 x - 1)/(x - 1)^6, {x, 0, 60}], x] (* Vincenzo Librandi, Oct 18 2013 *)

CROSSREFS

Sequence in context: A299053 A005289 A037255 * A001982 A129707 A320545

Adjacent sequences:  A027655 A027656 A027657 * A027659 A027660 A027661

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified November 23 13:02 EST 2020. Contains 338590 sequences. (Running on oeis4.)