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A081729 Expansion of Sum(k>=0, x^(2^k)) + 1/(1+x). First differences of A007456 (gossip sequence) for n>1. 3
1, 0, 2, -1, 2, -1, 1, -1, 2, -1, 1, -1, 1, -1, 1, -1, 2, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 2, -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, 2, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

For n>1: a(n) = 2, if n is power of 2; a(n) =- 1, if n odd; a(n) = 1 otherwise.

The absolute values of a(n) for n>=2 equal the q(n) sequence of the Eta triangle A160464. - Johannes W. Meijer, May 24 2009

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..65536

FORMULA

a(n) = A209229(n) + A033999(n). - Reinhard Zumkeller, Apr 03 2014

PROG

(Haskell)

a081729 n = a209229 n + a033999(n)

-- Reinhard Zumkeller, Apr 03 2014

CROSSREFS

Cf. A033999, A043529, A160464, A209229.

Sequence in context: A319395 A194636 A286299 * A219157 A080215 A266871

Adjacent sequences:  A081726 A081727 A081728 * A081730 A081731 A081732

KEYWORD

sign,easy

AUTHOR

Ralf Stephan, Apr 06 2003

EXTENSIONS

Erroneous formula removed by Antti Karttunen, Sep 14 2017

STATUS

approved

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Last modified July 26 01:49 EDT 2021. Contains 346294 sequences. (Running on oeis4.)