A134301 Periodic sequence (0, 2, 6, 2, 0).

0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0, 0, 2, 6, 2, 0

Offset

0,2

Comments

Also: twice the partial sums of A117444. - R. J. Mathar, Feb 01 2008

Links

Table of n, a(n) for n=0..64.

Rozsa Peter, Leon Harkleroad, Mathematics is Beautiful, Math. Intellig., 12 (No. 1, 1990), 58-64.

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

Formula

a(n) = n(n+1) mod 10

O.g.f.: -2/(x-1)+(2*x^3+2*x^2-2*x-2)/(1+x+x^2+x^3+x^4). a(n)=a(n-5). - R. J. Mathar, Feb 01 2008

Mathematica

PadRight[{}, 70, {0, 2, 6, 2, 0}] (* Harvey P. Dale, Mar 22 2012 *)

Prog

(PARI) a(n)=[0, 2, 6, 2, 0][n%5+1] \\ Charles R Greathouse IV, Jul 13 2016

Crossrefs

Sequence in context: A117214 A185972 A182918 * A168294 A363737 A004544

Adjacent sequences: A134298 A134299 A134300 * A134302 A134303 A134304

Keyword

nonn,easy

Author

Franz Vrabec, Jan 30 2008

Status

approved