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A010721 Period 2: repeat (5,10). 2
5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10, 5, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..65.

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

FORMULA

a(n) = -5/2*(-1)^n + 15/2 = 10*(n mod 2) + 5*[(n+1) mod 2]. - Paolo P. Lava, Oct 27 2006

From R. J. Mathar, Oct 20 2008: (Start)

a(n) = 5*A000034(n).

G.f.: 5(1+2x)/((1-x)(1+x)). (End)

MATHEMATICA

Table[5 + 5 Mod[n, 2], {n, 0, 50}] (* Jinyuan Wang, Feb 26 2020 *)

PROG

(PARI) a(n)=n%2*5+5 \\ Charles R Greathouse IV, Jul 13 2016

CROSSREFS

Cf. A176325.

Sequence in context: A276652 A137404 A110643 * A046795 A337545 A229793

Adjacent sequences:  A010718 A010719 A010720 * A010722 A010723 A010724

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified June 24 21:50 EDT 2021. Contains 345433 sequences. (Running on oeis4.)