A070437 a(n) = n^2 mod 14.

0, 1, 4, 9, 2, 11, 8, 7, 8, 11, 2, 9, 4, 1, 0, 1, 4, 9, 2, 11, 8, 7, 8, 11, 2, 9, 4, 1, 0, 1, 4, 9, 2, 11, 8, 7, 8, 11, 2, 9, 4, 1, 0, 1, 4, 9, 2, 11, 8, 7, 8, 11, 2, 9, 4, 1, 0, 1, 4, 9, 2, 11, 8, 7, 8, 11, 2, 9, 4, 1, 0, 1, 4, 9, 2, 11, 8, 7, 8, 11, 2, 9, 4, 1, 0, 1, 4, 9, 2, 11, 8, 7, 8, 11, 2, 9, 4

Offset: 0

Author

N. J. A. Sloane, May 12 2002

Keywords

• nonn
• easy

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, 1).

Crossrefs

Cf. A070434, A070435, A070436.

Programs

Mathematica

Table[Mod[n^2,14],{n,0,200}] (* Vladimir Joseph Stephan Orlovsky, Apr 21 2011 *)
PowerMod[Range[0,100],2,14] (* Harvey P. Dale, Dec 02 2014 *)

PARI

a(n)=n^2%14 \\ Charles R Greathouse IV, Apr 06 2016

Formula

G.f.: -x*(1 +4*x +9*x^2 +2*x^3 +11*x^4 +8*x^5 +7*x^6 +8*x^7 +11*x^8 +2*x^9 +9*x^10 +4*x^11 +x^12) / ((x-1)*(1+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)). - R. J. Mathar, Jul 27 2015

a(n) = a(n-14). - G. C. Greubel, Mar 24 2016