A132380 Period 8: repeat [0, 0, 1, 1, 0, 0, -1, -1].

0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, -1, -1

Offset

0,1

Links

Antti Karttunen, Table of n, a(n) for n = 0..8191

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

Formula

O.g.f.: x^2*(1+x)/(1+x^4). - R. J. Mathar, Apr 06 2008

For n > 0, a(n) = A109247(n)/-3. - Antti Karttunen, Aug 12 2017

a(n) = (1/2)*(1-(-1)^floor(n/2))*(-1)^floor(n/4). - Wesley Ivan Hurt, Aug 31 2019

Mathematica

PadRight[{}, 120, {0, 0, 1, 1, 0, 0, -1, -1}] (* Harvey P. Dale, Mar 17 2016 *)

Prog

(PARI) a(n)=[0, 0, 1, 1, 0, 0, -1, -1][n%8+1] \\ Charles R Greathouse IV, Jun 02 2011
(Scheme) (define (A132380 n) (list-ref '(0 0 1 1 0 0 -1 -1) (modulo n 8))) ;; Antti Karttunen, Aug 12 2017

Crossrefs

Cf. A109247.

Sequence in context: A339824 A278587 A188257 * A021913 A285501 A288551

Adjacent sequences: A132377 A132378 A132379 * A132381 A132382 A132383

Keyword

sign,easy,less

Author

Paul Curtz, Nov 10 2007

Status

approved