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A099991 a(n) = Moebius(2n). 2
-1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, -1, 0, 1, 0, 1, 0, -1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, -1, 0, -1, 0, 1, 0, -1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 1, 0, -1, 0, -1, 0, 1, 0, 1, 0, 0, 0, -1, 0, 1, 0, -1, 0, 1, 0, 1, 0, 0, 0, -1, 0, 1, 0, 0, 0, 1, 0, -1, 0, -1, 0, 1, 0, -1, 0, -1, 0, -1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

b(n) = -a(n) is multiplicative with b(2^e) = 0, b(p) = -1 if p >= 3, 0 otherwise. - David W. Wilson, Jun 12 2005

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = mu(2n) = A008683(2n). - Wesley Ivan Hurt, Dec 17 2013

MAPLE

with(numtheory); A099991:=n->mobius(2*n); seq(A099991(n), n=1..100); # Wesley Ivan Hurt, Dec 17 2013

MATHEMATICA

lst={}; Do[AppendTo[lst, MoebiusMu[n]], {n, 0, 6!, 2}]; lst (* Vladimir Joseph Stephan Orlovsky, Sep 20 2008 *)

MoebiusMu[2*Range[110]] (* Harvey P. Dale, Jul 13 2012 *)

PROG

(PARI) A099991(n) = moebius(2*n); \\ Antti Karttunen, Sep 14 2017

CROSSREFS

Bisection of A008683. Cf. A099990.

Sequence in context: A100060 A147850 A080545 * A091069 A318608 A087003

Adjacent sequences:  A099988 A099989 A099990 * A099992 A099993 A099994

KEYWORD

sign,easy

AUTHOR

N. J. A. Sloane, Nov 20 2004

STATUS

approved

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Last modified December 16 15:11 EST 2018. Contains 318172 sequences. (Running on oeis4.)