A070449 a(n) = n^2 mod 27.

0, 1, 4, 9, 16, 25, 9, 22, 10, 0, 19, 13, 9, 7, 7, 9, 13, 19, 0, 10, 22, 9, 25, 16, 9, 4, 1, 0, 1, 4, 9, 16, 25, 9, 22, 10, 0, 19, 13, 9, 7, 7, 9, 13, 19, 0, 10, 22, 9, 25, 16, 9, 4, 1, 0, 1, 4, 9, 16, 25, 9, 22, 10, 0, 19, 13, 9, 7, 7, 9, 13, 19, 0, 10, 22, 9, 25, 16, 9, 4, 1, 0, 1, 4, 9, 16

Offset

0,3

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, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).

Formula

a(n) = a(n-27). - G. C. Greubel, Mar 24 2016

G.f.:(x + 4*x^2 + 9*x^3 + 16*x^4 + 25*x^5 + 9*x^6 + 22*x^7 + 10*x^8 + 19*x^10 + 13*x^11 + 9*x^12 + 7*x^13 + 7*x^14 + 9*x^15 + 13*x^16 + 19*x^17 + 10*x^19 + 22*x^20 + 9*x^21 + 25*x^22 + 16*x^23 + 9*x^24 + 4*x^25 + x^26)/(1 - x^27). - Vincenzo Librandi, Mar 25 2016

Mathematica

Table[Mod[n^2, 27], {n, 0, 200}] (* Vladimir Joseph Stephan Orlovsky, Apr 23 2011 *)
PowerMod[Range[0, 100], 2, 27] (* or *) PadRight[{}, 100, {0, 1, 4, 9, 16, 25, 9, 22, 10, 0, 19, 13, 9, 7, 7, 9, 13, 19, 0, 10, 22, 9, 25, 16, 9, 4, 1}] (* Harvey P. Dale, Dec 17 2023 *)

Prog

(PARI) a(n)=n^2%27 \\ Charles R Greathouse IV, Apr 06 2016

Crossrefs

Sequence in context: A357556 A070451 A070450 * A357408 A070448 A081403

Adjacent sequences: A070446 A070447 A070448 * A070450 A070451 A070452

Keyword

nonn,easy

Author

N. J. A. Sloane, May 12 2002

Status

approved