A070512 a(n) = n^4 mod 7.

0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2, 4, 4, 2, 1, 0, 1, 2

Offset

0,3

Comments

Equivalently: n^(4*m + 4) mod 7. - G. C. Greubel, Apr 01 2016

Links

Table of n, a(n) for n=0..100.

Formula

From G. C. Greubel, Apr 01 2016: (Start)

a(n) = a(n-7).

G.f.: x*(1 +2*x +4*x^2 +2*x^4 + x^5)/(1 - x^7).

Mathematica

PowerMod[Range[0, 100], 4, 7] (* G. C. Greubel, Apr 01 2016 *)

Prog

(Sage) [power_mod(n, 4, 7)for n in range(0, 101)] # Zerinvary Lajos, Oct 30 2009
(Magma) [Modexp(n, 4, 7): n in [0..100]]; // Vincenzo Librandi, Apr 02 2016
(PARI) a(n)=n^4%7 \\ Charles R Greathouse IV, Apr 06 2016

Crossrefs

Sequence in context: A058923 A107500 A108620 * A156346 A156283 A126123

Adjacent sequences: A070509 A070510 A070511 * A070513 A070514 A070515

Keyword

nonn,easy

Author

N. J. A. Sloane, May 13 2002

Status

approved