A070444 a(n) = n^2 mod 22.

0, 1, 4, 9, 16, 3, 14, 5, 20, 15, 12, 11, 12, 15, 20, 5, 14, 3, 16, 9, 4, 1, 0, 1, 4, 9, 16, 3, 14, 5, 20, 15, 12, 11, 12, 15, 20, 5, 14, 3, 16, 9, 4, 1, 0, 1, 4, 9, 16, 3, 14, 5, 20, 15, 12, 11, 12, 15, 20, 5, 14, 3, 16, 9, 4, 1, 0, 1, 4, 9, 16, 3, 14, 5, 20, 15, 12, 11, 12, 15, 20, 5

Offset

0,3

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..3000

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1).

Formula

From R. J. Mathar, Jul 27 2015: (Start)

a(n) = a(n-22).

G.f.: -x*(1 +4*x +9*x^2 +16*x^3 +3*x^4 +14*x^5 +5*x^6 +20*x^7 +15*x^8 +12*x^9 +11*x^10 +12*x^11 +15*x^12 +20*x^13 +5*x^14 +14*x^15 +3*x^16 +16*x^17 +9*x^18 +4*x^19+x^20) / ( (x-1) *(1+x^10+x^9+x^8+x^7+x^6+x^5+x^4+x^3+x^2+x) *(1+x) *(1-x+x^2-x^3+x^4-x^5+x^6-x^7+x^8-x^9+x^10) ). (End)

Mathematica

Table[Mod[n^2, 22], {n, 0, 200}] (* Vladimir Joseph Stephan Orlovsky, Apr 23 2011 *)
PowerMod[Range[0, 120], 2, 22] (* or *) PadRight[{}, 120, {0, 1, 4, 9, 16, 3, 14, 5, 20, 15, 12, 11, 12, 15, 20, 5, 14, 3, 16, 9, 4, 1}] (* Harvey P. Dale, May 28 2021 *)

Prog

(Maxima) makelist(power_mod (n, 2, 22), n, 0, 81); /* Bruno Berselli, May 25 2011 */
(Magma) [n^2 mod (22): n in [0..80]]; // Vincenzo Librandi, May 26 2011
(PARI) a(n)=n^2%22 \\ Charles R Greathouse IV, Apr 06 2016

Crossrefs

Sequence in context: A070446 A258682 A070445 * A120866 A070443 A279403

Adjacent sequences: A070441 A070442 A070443 * A070445 A070446 A070447

Keyword

nonn,easy

Author

N. J. A. Sloane, May 12 2002

Status

approved