OFFSET
0,3
COMMENTS
It is also true that a(n) = n^(4k+3) mod 15 holds any k. - Gary Detlefs, Dec 15 2021
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,0,0,0,0,0,1).
FORMULA
From G. C. Greubel, Mar 28 2016: (Start)
a(n) = a(n-15).
G.f.: (-x -8*x^2 -12*x^3 -4*x^4 -5*x^5 -6*x^6 -13*x^7 -2*x^8 -9*x^9 - 10*x^10 -11*x^11 -3*x^12 -7*x^13 -14*x^14)/(-1 + x^15). (End)
MATHEMATICA
PowerMod[Range[0, 90], 3, 15] (* or *) PadRight[{}, 90, {0, 1, 8, 12, 4, 5, 6, 13, 2, 9, 10, 11, 3, 7, 14}] (* Harvey P. Dale, Jan 27 2014 *)
Table[Mod[n^3, 15], {n, 0, 100}] (* Vincenzo Librandi, Jun 19 2014 *)
PROG
(Sage) [power_mod(n, 3, 15) for n in range(0, 90)] # Zerinvary Lajos, Oct 29 2009
(Magma) [Modexp(n, 3, 15): n in [0..100]]; // Vincenzo Librandi, Mar 28 2016
(PARI) a(n)=n^3%15 \\ Charles R Greathouse IV, Apr 06 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, May 12 2002
STATUS
approved