A017546 (12n+2)^2.

4, 196, 676, 1444, 2500, 3844, 5476, 7396, 9604, 12100, 14884, 17956, 21316, 24964, 28900, 33124, 37636, 42436, 47524, 52900, 58564, 64516, 70756, 77284, 84100, 91204, 98596, 106276, 114244, 122500

Offset

0,1

Links

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

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

Formula

G.f.: 4*(1+46*x+25*x^2)/(1-x)^3. - Vincenzo Librandi, Jul 07 2012

a(n) = 3*a(n-1) -3*a(n-2) +a(n-3). - Vincenzo Librandi, Jul 07 2012

Mathematica

CoefficientList[Series[4*(1+46*x+25*x^2)/(1-x)^3, {x, 0, 50}], x] (* Vincenzo Librandi, Jul 07 2012 *)
LinearRecurrence[{3, -3, 1}, {4, 196, 676}, 40] (* Harvey P. Dale, Oct 19 2012 *)

Prog

(Magma) I:=[4, 196, 676]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+Self(n-3): n in [1..50]]; // Vincenzo Librandi, Jul 07 2012
(PARI) a(n)=(12*n+2)^2 \\ Charles R Greathouse IV, Jun 17 2017

Crossrefs

Sequence in context: A028370 A042127 A219163 * A144044 A221197 A180991

Adjacent sequences: A017543 A017544 A017545 * A017547 A017548 A017549

Keyword

nonn,easy

Author

N. J. A. Sloane.

Status

approved