A187466 a(n) = 9^n mod 11.

1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1, 9, 4, 3, 5, 1

Offset: 0

Author

M. F. Hasler, Mar 10 2011

Keywords

• nonn
• easy

Comments

Period 5: repeat [1, 9, 4, 3, 5].

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,1).

Crossrefs

Cf. A010691, A036117, A048271, A070341, A070367, A070392, A070404, A168429.

Programs

Maple

A187466:=n->9^n mod 11: seq(A187466(n), n=0..100); # Wesley Ivan Hurt, Jun 11 2016

Mathematica

PowerMod[9, Range[0, 100], 11] (* Wesley Ivan Hurt, Jun 11 2016 *)

PARI

a(n)=lift(Mod(9,11)^n) \\ Charles R Greathouse IV, Mar 22 2016

Formula

G.f.: (5*x^4 + 3*x^3 + 4*x^2 + 9*x + 1)/(1 - x^5). - Chai Wah Wu, Jun 04 2016

a(n) = a(n-5) for n>4. - Wesley Ivan Hurt, Jun 11 2016