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A281048 Expansion of x*(1 - x)*Product_{k>=0} (1 + x^(2^k) - x^(2^(k+1))). 1
1, 0, -1, 1, -2, 1, 1, 0, -3, 1, 2, -1, 1, 0, -1, 1, -4, 1, 3, -2, 3, -1, -2, 1, 1, 0, -1, 1, -2, 1, 1, 0, -5, 1, 4, -3, 5, -2, -3, 1, 4, -1, -3, 2, -3, 1, 2, -1, 1, 0, -1, 1, -2, 1, 1, 0, -3, 1, 2, -1, 1, 0, -1, 1, -6, 1, 5, -4, 7, -3, -4, 1, 7, -2, -5, 3, -4, 1, 3, -2, 5, -1, -4, 3, -5, 2, 3, -1, -4, 1, 3, -2, 3, -1, -2, 1, 1, 0, -1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

First differences of A005590.

LINKS

Table of n, a(n) for n=1..100.

Michael Gilleland, Some Self-Similar Integer Sequences

Ilya Gutkovskiy, Extended graphical example

R. Stephan, Divide-and-conquer generating functions. I. Elementary sequences, arXiv:math/0307027 [math.CO], 2003.

FORMULA

G.f.: x*(1 - x)*Product_{k>=0} (1 + x^(2^k) - x^(2^(k+1))).

MATHEMATICA

Rest[CoefficientList[Series[x (1 - x) Product[1 + x^2^k - x^2^(k + 1), {k, 0, 15}], {x, 0, 100}], x]]

Differences[a[0] = 0; a[1] = 1; a[n_] := a[n] = If[OddQ[n], a[(n-1)/2 + 1] - a[(n-1)/2], a[n/2]]; Table[a[n], {n, 0, 100}]]

CROSSREFS

Cf. A005590, A070990, A182093.

Sequence in context: A129334 A116399 A116405 * A029352 A055168 A085144

Adjacent sequences:  A281045 A281046 A281047 * A281049 A281050 A281051

KEYWORD

sign

AUTHOR

Ilya Gutkovskiy, Feb 27 2017

STATUS

approved

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Last modified October 19 22:55 EDT 2019. Contains 328244 sequences. (Running on oeis4.)