A010681 Period 2: repeat (0,10).

0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10, 0, 10

Offset

0,2

Links

Table of n, a(n) for n=0..71.

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

Formula

a(n) = 5*(1 - (-1)^n) = 10*(n mod 2). - Paolo P. Lava, Oct 20 2006

G.f.: 10*x/((1-x)*(1+x)). - R. J. Mathar, Nov 21 2011

From Elmo R. Oliveira, Sep 28 2025: (Start)

E.g.f.: 10*sinh(x).

a(n) = a(n-2). (End)

Mathematica

PadRight[{}, 120, {0, 10}] (* Harvey P. Dale, Jan 15 2016 *)

Prog

(PARI) a(n)=n%2*10 \\ Charles R Greathouse IV, Jul 13 2016

Crossrefs

Cf. A000035.

Sequence in context: A063741 A320227 A284780 * A095418 A055961 A341504

Adjacent sequences: A010678 A010679 A010680 * A010682 A010683 A010684

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved