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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

G.f.: 5(1+2x)/((1-x)(1+x)). a(n)=5*A000034(n). [From R. J. Mathar, Oct 20 2008]

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 A229793 A205854

Adjacent sequences:  A010718 A010719 A010720 * A010722 A010723 A010724

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified December 10 13:27 EST 2016. Contains 279004 sequences.