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A112347
Kronecker symbol (-1, n) except a(0) = 0.
2
0, 1, 1, -1, 1, 1, -1, -1, 1, 1, 1, -1, -1, 1, -1, -1, 1, 1, 1, -1, 1, 1, -1, -1, -1, 1, 1, -1, -1, 1, -1, -1, 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, 1, -1, -1, 1, -1, -1, -1, 1, 1, -1, 1, 1, -1, -1, -1, 1, 1, -1, -1, 1, -1, -1, 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, 1, -1, -1, 1, -1, -1, 1, 1, 1, -1, 1, 1, -1, -1, -1, 1, 1, -1, -1, 1, -1, -1, -1, 1, 1, -1, 1, 1, -1
OFFSET
0,1
LINKS
J.-P. Allouche and J. Shallit, On three conjectures of P. Barry, arxiv preprint arXiv:2006.04708 [math.NT], June 8 2020.
FORMULA
Multiplicative with a(2^e) = 1, a(p^e) = (-1)^(e(p-1)/2) if p>2.
a(2n) = a(n), a(4*n + 1) = 1, a(4*n + 3) = -1. a(-n) = -a(n).
a(n) = A034947(n) unless n=0.
EXAMPLE
x + x^2 - x^3 + x^4 + x^5 - x^6 - x^7 + x^8 + x^9 + x^10 - x^11 - x^12 + x^13 + ...
MATHEMATICA
Join[{0}, KroneckerSymbol[-1, Range[110]]] (* Harvey P. Dale, Jun 02 2019 *)
PROG
(PARI) {a(n) = if( n, kronecker( -1, n))}
CROSSREFS
Cf. A034947.
First differences of A005811.
Sequence in context: A070238 A062157 A103131 * A057427 A178334 A000007
KEYWORD
sign,mult
AUTHOR
Michael Somos, Sep 12 2005
STATUS
approved