A017126 a(n) = (8*n + 5)^2.

25, 169, 441, 841, 1369, 2025, 2809, 3721, 4761, 5929, 7225, 8649, 10201, 11881, 13689, 15625, 17689, 19881, 22201, 24649, 27225, 29929, 32761, 35721, 38809, 42025, 45369, 48841, 52441, 56169, 60025, 64009, 68121, 72361, 76729, 81225, 85849, 90601, 95481, 100489, 105625

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..10000

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

Formula

G.f.: ( -25 - 94*x - 9*x^2 ) / (x-1)^3. - R. J. Mathar, May 08 2015

E.g.f.: exp(x)*(25 + 144*x + 64*x^2). - Stefano Spezia, Oct 28 2023

Mathematica

(8Range[0, 40]+5)^2  (* Harvey P. Dale, Mar 12 2011 *)

Prog

(Magma) [(8*n+5)^2: n in [0..35] ]; // Vincenzo Librandi, Jul 21 2011
(PARI) a(n)=(8*n+5)^2 \\ Charles R Greathouse IV, Jun 17 2017

Crossrefs

Cf. A004770.

Sequence in context: A360280 A198436 A080109 * A007204 A120096 A115330

Adjacent sequences: A017123 A017124 A017125 * A017127 A017128 A017129

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved