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A059778 Expansion of 1 / product((1+q^(2*n+3))/(1-q^(2*n+2)), n=0..inf). 1
1, 0, -1, -1, -1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, -1, -1, 0, 0, 0, 0, -1, -1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

a(n) = (-1)^n*(t(n)-t(n-1)), n>0, where t(n) = A010054(n) is characteristic function of triangular numbers. - Vladeta Jovovic, Sep 22 2002

REFERENCES

G. E. Andrews, Three-quadrant Ferrers graphs, Indian J. Math., 42 (No. 1, 2000), 1-7.

LINKS

Table of n, a(n) for n=0..92.

CROSSREFS

Cf. A059777.

Sequence in context: A259599 A070749 A285341 * A104521 A317198 A131379

Adjacent sequences:  A059775 A059776 A059777 * A059779 A059780 A059781

KEYWORD

sign

AUTHOR

N. J. A. Sloane, Feb 21 2001

STATUS

approved

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Last modified July 16 04:26 EDT 2019. Contains 325064 sequences. (Running on oeis4.)