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A157657 a(1) = 1, a(n) = -mu(n) for n >= 2. 3
1, 1, 1, 0, 1, -1, 1, 0, 0, -1, 1, 0, 1, -1, -1, 0, 1, 0, 1, 0, -1, -1, 1, 0, 0, -1, 0, 0, 1, 1, 1, 0, -1, -1, -1, 0, 1, -1, -1, 0, 1, 1, 1, 0, 0, -1, 1, 0, 0, 0, -1, 0, 1, 0, -1, 0, -1, -1, 1, 0, 1, -1, 0, 0, -1, 1, 1, 0, -1, 1, 1, 0, 1, -1, 0, 0, -1, 1, 1, 0, 0, -1, 1, 0, -1, -1, -1, 0, 1, 0, -1, 0, -1, -1, -1, 0, 1, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Apparently the Dirichlet inverse of A114006. [R. J. Mathar, Jul 15 2010]
Not multiplicative; for example a(2)*a(3) != a(6). - R. J. Mathar, Mar 31 2012
LINKS
PROG
(PARI) a(n)=if(n==1, 1, -moebius(n)); \\ Joerg Arndt, Aug 25 2014
(Scheme) (define (A157657 n) (if (= 1 n) 1 (- (A008683 n)))) ;; Antti Karttunen, Jul 26 2017
CROSSREFS
Cf. A008683, A157658 (same except for a(1)).
Sequence in context: A008683 A008966 A080323 * A359155 A069158 A353559
KEYWORD
sign
AUTHOR
Jaroslav Krizek, Mar 03 2009
EXTENSIONS
Added more terms, Joerg Arndt, Aug 25 2014
STATUS
approved

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Last modified May 13 02:41 EDT 2024. Contains 372497 sequences. (Running on oeis4.)