A033578 a(n) = (3*n - 1)*(4*n - 1).

1, 6, 35, 88, 165, 266, 391, 540, 713, 910, 1131, 1376, 1645, 1938, 2255, 2596, 2961, 3350, 3763, 4200, 4661, 5146, 5655, 6188, 6745, 7326, 7931, 8560, 9213, 9890, 10591, 11316, 12065, 12838, 13635, 14456, 15301, 16170, 17063, 17980, 18921, 19886, 20875

Offset

0,2

Links

Nathaniel Johnston, Table of n, a(n) for n = 0..5000

Index entries for linear recurrences with constant coefficients, signature (3,-3,1).

Formula

From G. C. Greubel, Oct 09 2019: (Start)

G.f.: (1 + 3*x +20*x^2)/(1-x)^3.

E.g.f.: (1 + 5*x + 12*x^2)*exp(x). (End)

Maple

seq((3*n-1)*(4*n-1), n=0..50); # Nathaniel Johnston, Jun 26 2011

Mathematica

Table[(3*n-1)*(4*n-1), {n, 0, 50}] (* Vladimir Joseph Stephan Orlovsky, Jun 26 2011 *)

Prog

(PARI) a(n)=(3*n-1)*(4*n-1) \\ Charles R Greathouse IV, Jun 17 2017
(Magma) [(3*n-1)*(4*n-1): n in [0..50]]; // G. C. Greubel, Oct 09 2019
(Sage) [(3*n-1)*(4*n-1) for n in (0..50)] # G. C. Greubel, Oct 09 2019
(GAP) List([0..50], n-> (3*n-1)*(4*n-1)); # G. C. Greubel, Oct 09 2019

Crossrefs

Cf. A033577.

Sequence in context: A009583 A369351 A370091 * A101077 A094952 A024526

Adjacent sequences: A033575 A033576 A033577 * A033579 A033580 A033581

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved