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A111113
a(2^m) = 1, a(2^m+1) = -1 (m>0), otherwise a(n) = 0.
1
0, 0, 1, -1, 1, -1, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
0,1
LINKS
A. G. Postnikov, Tauberian Theory and Its Applications, Proc. Steklov. Inst. Math., 144 (1979), translated as Issue 2, 1980. See p. 29.
A. Renyi, On a Tauberian theorem of O. Szasz, Acta Univ. Szeged. Sect. Sci. Math., 11 (1946), 119-123.
FORMULA
Euler transform of A079559 is sequence offset -1. - Michael Somos, Aug 03 2009
G.f.: (1 - x) * (Sum_{k>0} x^(2^k)). - Michael Somos, Aug 03 2009
|a(n)| = A001683(n)(mod 2) for n > 1. - John M. Campbell, Apr 01 2018
EXAMPLE
G.f. = x^2 - x^3 + x^4 - x^5 + x^8 - x^9 + x^16 - x^17 + x^32 - x^33 + ...
PROG
(PARI) {a(n) = if( n<2, 0, [1, -1, 0] [1 + min(2, n - 2^(length(binary(n)) - 1))] )} /* Michael Somos, Aug 03 2009 */
(PARI) {a(n) = if( n<2, 0, if( n%2, -a(n - 1), n == 2^valuation(n, 2)))} /* Michael Somos, Aug 03 2009 */
CROSSREFS
Sequence in context: A339051 A234045 A238468 * A095190 A131735 A131736
KEYWORD
sign
AUTHOR
N. J. A. Sloane, Oct 15 2005
STATUS
approved