A002089 a(n) = 11*4^n.

11, 44, 176, 704, 2816, 11264, 45056, 180224, 720896, 2883584, 11534336, 46137344, 184549376, 738197504, 2952790016, 11811160064, 47244640256, 188978561024, 755914244096, 3023656976384, 12094627905536, 48378511622144, 193514046488576, 774056185954304, 3096224743817216

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Comments

Subsequence of A000069, the odious numbers. - Reinhard Zumkeller, Aug 26 2007

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..500
• Tanya Khovanova, Recursive Sequences.
• Index entries for linear recurrences with constant coefficients, signature (4).

Crossrefs

Bisection of A005015. Half the first differences of A072261.

Programs

Magma

[11*4^n: n in [0..30]]; // Vincenzo Librandi, May 31 2011

Maple

A002089:=n->11*4^n; seq(A002089(n), n=0..100); # Wesley Ivan Hurt, Nov 12 2013

Mathematica

11*4^Range[0, 100] (* Vladimir Joseph Stephan Orlovsky, Jun 09 2011 *)
NestList[4#&,11,30] (* Harvey P. Dale, Jun 19 2014 *)

PARI

a(n)=11*4^n \\ Charles R Greathouse IV, Apr 18 2012

Formula

From Philippe Deléham, Nov 23 2008: (Start)

a(n) = 4*a(n-1); a(0)=11.

G.f.: 11/(1-4*x). (End)

a(n) = 11*A000302(n). - Michel Marcus, Nov 13 2013

From Elmo R. Oliveira, Apr 02 2025: (Start)

E.g.f.: 11*exp(4*x).

a(n) = A005015(2*n). (End)