A017414 (11n+2)^2.

4, 169, 576, 1225, 2116, 3249, 4624, 6241, 8100, 10201, 12544, 15129, 17956, 21025, 24336, 27889, 31684, 35721, 40000, 44521, 49284, 54289, 59536, 65025, 70756, 76729, 82944, 89401, 96100, 103041

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+157*x+81*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+157*x+81*x^2)/(1-x)^3, {x, 0, 50}], x] (* Vincenzo Librandi, Jul 07 2012 *)

Prog

(Magma) I:=[4, 169, 576]; [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)=(11*n+2)^2 \\ Charles R Greathouse IV, Jun 17 2017

Crossrefs

Sequence in context: A061710 A262687 A177005 * A051476 A283566 A221083

Adjacent sequences: A017411 A017412 A017413 * A017415 A017416 A017417

Keyword

nonn,easy

Author

N. J. A. Sloane.

Status

approved