A168429 a(n) = 4^n mod 11.

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

Offset: 0

Author

Zerinvary Lajos, Nov 25 2009

Keywords

• nonn
• easy

Comments

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

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..1000
• Joshua Ide and Marc S. Renault, Power Fibonacci Sequences, Fib. Q. 50(2), 2012, 175-179.
• Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,1).

Crossrefs

See also A036117.

Programs

Mathematica

Table[Mod[4^n, 11], {n, 0, 50}] (* G. C. Greubel, Mar 05 2016 *)
PowerMod[4,Range[0,100],11] (* or *) PadRight[{},100,{1,4,5,9,3}] (* Harvey P. Dale, Jul 02 2021 *)

PARI

a(n)=4^n%11 \\ Charles R Greathouse IV, Oct 16 2015

Sage

[power_mod(4, n, 11) for n in range(0, 95)]

Formula

a(n) = a(n-5). G.f.: (1+4*x+5*x^2+9*x^3+3*x^4)/((1-x) * (1+x+x^2+x^3+x^4)). - R. J. Mathar, Apr 13 2010