A021499 Decimal expansion of 1/495.

0, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0

Offset

0,3

Comments

0, then repeat 0, 2. - Arkadiusz Wesolowski, Jul 22 2011

Links

Table of n, a(n) for n=0..85.

Index entries for periodic sequences.

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

Formula

a(n) = 1 + (-1)^n - 2*0^n = (-1 - A033999(n))*A062157(n). - Arkadiusz Wesolowski, Jul 22 2011

G.f.: 2*x^2/(1-x^2). - Bruno Berselli, Jul 22 2011

Mathematica

Join[{0, 0}, RealDigits[1/495, 10, 120][[1]]] (* or *) PadRight[{0}, 120, {2, 0}] (* Harvey P. Dale, Dec 13 2020 *)

Prog

(PARI) a(n)=if(n, 2-n%2*2, 0) \\ Charles R Greathouse IV, May 28 2026
(PARI) 1/495. \\ Charles R Greathouse IV, May 28 2026

Crossrefs

A010673 shifted right.

Cf. A033999, A062157.

Sequence in context: A277162 A230103 A267602 * A176742 A010673 A084099

Adjacent sequences: A021496 A021497 A021498 * A021500 A021501 A021502

Keyword

nonn,cons,easy

Author

N. J. A. Sloane

Status

approved