A140677 a(n) = n*(3*n + 8).

0, 11, 28, 51, 80, 115, 156, 203, 256, 315, 380, 451, 528, 611, 700, 795, 896, 1003, 1116, 1235, 1360, 1491, 1628, 1771, 1920, 2075, 2236, 2403, 2576, 2755, 2940, 3131, 3328, 3531, 3740, 3955, 4176, 4403, 4636, 4875, 5120, 5371, 5628

Offset: 0

Author

Omar E. Pol, May 22 2008

Keywords

• easy
• nonn

Examples

			a(1) = 6*1 + 0 + 5 = 11; a(2) = 6*2 + 11 + 5 = 28; a(3) = 6*3 + 28 + 5 = 51. - _Vincenzo Librandi_, Aug 03 2010
		

Links

• G. C. Greubel, Table of n, a(n) for n = 0..5000
• Index entries for linear recurrences with constant coefficients, signature (3,-3,1).

Crossrefs

Cf. A033428, A045944, A140676, A067725, A140678, A067707, A140679, A140680, A140681, A140689.

Programs

Mathematica

Table[n(3n+8),{n,0,45}]  (* Harvey P. Dale, Feb 20 2011 *)

PARI

a(n)=n*(3*n+8) \\ Charles R Greathouse IV, Jun 17 2017

Formula

a(n) = 3*n^2 + 8*n.

a(n) = 6*n + a(n-1) + 5, with a(0)=0. - Vincenzo Librandi, Aug 03 2010

G.f.: x*(11 - 5*x)/(1 - x)^3. - Arkadiusz Wesolowski, Dec 24 2011

E.g.f.: (3*x^2 + 11*x)*exp(x). - G. C. Greubel, Jul 20 2017