A017377 a(n) = 10*n + 9.

9, 19, 29, 39, 49, 59, 69, 79, 89, 99, 109, 119, 129, 139, 149, 159, 169, 179, 189, 199, 209, 219, 229, 239, 249, 259, 269, 279, 289, 299, 309, 319, 329, 339, 349, 359, 369, 379, 389, 399, 409, 419, 429, 439, 449, 459, 469, 479, 489, 499, 509, 519, 529, 539

Offset

0,1

Comments

Numbers k such that k^k ends with 9. - Bruno Berselli, Dec 11 2018

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..5000

Tanya Khovanova, Recursive Sequences

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 979

Index entries for linear recurrences with constant coefficients, signature (2,-1).

Formula

a(n) = 10*n + 9; a(n) = 2*a(n-1) - a(n-2). - Vincenzo Librandi, May 29 2011

G.f.: ( 9+x ) / (x-1)^2 . - R. J. Mathar, Oct 16 2015

Mathematica

Range[9, 1000, 10] (* Vladimir Joseph Stephan Orlovsky, May 28 2011 *)

Prog

(Magma) [10*n+9: n in [0..60]]; // Vincenzo Librandi, May 29 2011
(PARI) a(n)=10*n+9 \\ Charles R Greathouse IV, Feb 12 2017

Crossrefs

Cf. A008592, A017365, A190876.

Sequence in context: A043525 A277596 A031499 * A363060 A330171 A189798

Adjacent sequences: A017374 A017375 A017376 * A017378 A017379 A017380

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved