A155120 a(n) = 2*(n^3 + n^2 + n - 1).

-2, 4, 26, 76, 166, 308, 514, 796, 1166, 1636, 2218, 2924, 3766, 4756, 5906, 7228, 8734, 10436, 12346, 14476, 16838, 19444, 22306, 25436, 28846, 32548, 36554, 40876, 45526, 50516, 55858

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..2000

Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).

Formula

a(n) = 2*(n^3 +n^2 +n -1).

G.f.: 2*(-1 +6*x -x^2 +2*x^3)/(1-x)^4.

E.g.f.: 2*(-1 + 3*x + 4*x^2 + x^3)*exp(x). - G. C. Greubel, Mar 25 2021

Maple

seq( 2*(n^3 +n^2 +n -1), n=0..40); # G. C. Greubel, Mar 25 2021

Mathematica

Table[-2 +2n +2n^2 +2n^3, {n, 0, 30}]
LinearRecurrence[{4, -6, 4, -1}, {-2, 4, 26, 76}, 40] (* Harvey P. Dale, Jun 06 2014 *)

Prog

(Magma) [2*(n^3+n^2+n-1): n in [0..40] ]; // Vincenzo Librandi, May 23 2011
(Sage) [2*(n^3 +n^2 +n -1) for n in (0..40)] # G. C. Greubel, Mar 25 2021

Crossrefs

Cf. A142463, A155121, A155122, A155123, A155124.

Sequence in context: A028386 A362001 A259374 * A356442 A144691 A367428

Adjacent sequences: A155117 A155118 A155119 * A155121 A155122 A155123

Keyword

sign,easy

Author

Roger L. Bagula, Jan 20 2009

Status

approved