A120846 a(n) = 3^n + 2^n + n.

2, 6, 15, 38, 101, 280, 799, 2322, 6825, 20204, 60083, 179206, 535549, 1602528, 4799367, 14381690, 43112273, 129271252, 387682651, 1162785774, 3487832997, 10462450376, 31385253935, 94151567458, 282446313721, 847322163900, 2541932937219, 7625731702742, 22877060890445

Offset

0,1

Links

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

Index entries for linear recurrences with constant coefficients, signature (7,-17,17,-6).

Formula

From Harvey P. Dale, Oct 24 2011: (Start)

a(0)=2, a(1)=6, a(2)=15, a(3)=38, a(n) = 7*a(n-1) - 17*a(n-2) + 17*a(n-3) - 6*a(n-4).

G.f.: (x^3+7*x^2-8*x+2)/((x-1)^2*(6*x^2-5*x+1)). (End)

E.g.f.: exp(x)*(x + exp(x) + exp(2*x)). - Elmo R. Oliveira, Mar 07 2025

Maple

A120846:=n->3^n+2^n+n: seq(A120846(n), n=0..40); # Wesley Ivan Hurt, Jan 21 2017

Mathematica

Table[3^n + 2^n + n, {n, 0, 30}] (* or *) LinearRecurrence[{7, -17, 17, -6}, {2, 6, 15, 38}, 30] (* Harvey P. Dale, Oct 24 2011 *)

Prog

(Magma) [3^n+2^n+n: n in [0..30]]; // Vincenzo Librandi, Feb 27 2013

Crossrefs

Cf. A000079, A001047, A007689.

Sequence in context: A153122 A109545 A191634 * A101522 A094969 A001674

Adjacent sequences: A120843 A120844 A120845 * A120847 A120848 A120849

Keyword

nonn,easy,changed

Author

Mohammad K. Azarian, Aug 18 2006

Extensions

Edited by Ray Chandler, Sep 06 2006

Status

approved