A070434 a(n) = n^2 mod 11.

0, 1, 4, 9, 5, 3, 3, 5, 9, 4, 1, 0, 1, 4, 9, 5, 3, 3, 5, 9, 4, 1, 0, 1, 4, 9, 5, 3, 3, 5, 9, 4, 1, 0, 1, 4, 9, 5, 3, 3, 5, 9, 4, 1, 0, 1, 4, 9, 5, 3, 3, 5, 9, 4, 1, 0, 1, 4, 9, 5, 3, 3, 5, 9, 4, 1, 0, 1, 4, 9, 5, 3, 3, 5, 9, 4, 1, 0, 1, 4, 9, 5, 3, 3, 5, 9, 4, 1, 0, 1, 4, 9, 5, 3, 3, 5, 9, 4, 1, 0, 1

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, 1).

Crossrefs

Cf. A010880, A070430, A070431, A070432.

Programs

Mathematica

Table[Mod[n^2,11],{n,0,200}] (* Vladimir Joseph Stephan Orlovsky, Apr 21 2011 *)

PARI

a(n)=n^2%11 \\ Charles R Greathouse IV, Apr 06 2016

Formula

From R. J. Mathar, Apr 20 2010: (Start)

a(n) = a(n-11).

G.f.: ( -x*(1+x)*(x^8+3*x^7+6*x^6-x^5+4*x^4-x^3+6*x^2+3*x+1) ) / ( (x-1)*(1+x+x^2+x^3+x^4+x^5+x^6+x^7+x^8+x^9+x^10) ). (End)

a(n) = A010880(n^2). - Michel Marcus, Mar 24 2016