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A070367
a(n) = 5^n mod 11.
5
1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1, 5, 3, 4, 9, 1
OFFSET
0,2
COMMENTS
Period 5: repeat [1, 5, 3, 4, 9].
FORMULA
From R. J. Mathar, Apr 20 2010: (Start)
a(n) = a(n-5).
G.f.: ( -1-5*x-3*x^2-4*x^3-9*x^4 ) / ( (x-1)*(1+x+x^2+x^3+x^4) ). (End)
MATHEMATICA
Table[Mod[5^n, 11], {n, 0, 100}] (* G. C. Greubel, Mar 05 2016 *)
PROG
(Sage) [power_mod(5, n, 11)for n in range(0, 101)] # Zerinvary Lajos, Nov 25 2009
(Magma) &cat[[1, 5, 3, 4, 9]^^20]; // Vincenzo Librandi, Mar 06 2016
(PARI) a(n)=lift(Mod(5, 11)^n) \\ Charles R Greathouse IV, Mar 22 2016
CROSSREFS
Cf. A000351.
Sequence in context: A319053 A109681 A196406 * A086308 A229943 A198132
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, May 12 2002
STATUS
approved