login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A291646 Expansion of the series reversion of -1 + Product_{k>=1} (1 + x^(2*k-1)). 0
1, 0, -1, -1, 2, 6, -1, -29, -32, 108, 311, -185, -1991, -1590, 9468, 22163, -26645, -170511, -70359, 955734, 1755790, -3561052, -16020532, 309754, 102695477, 141637053, -463468990, -1567907433, 806541136, 11367276801, 10768399120, -59447130815, -155142592628, 172852194214, 1273466836673 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Reversion of g.f. (with constant term omitted) for A000700.

LINKS

Table of n, a(n) for n=1..35.

N. J. A. Sloane, Transforms

Eric Weisstein's World of Mathematics, Series Reversion

Index entries for reversions of series

FORMULA

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

MATHEMATICA

nmax = 35; Rest[CoefficientList[InverseSeries[Series[-1 + Product[1 + x^(2 k - 1), {k, 1, nmax}], {x, 0, nmax}], x], x]]

nmax = 35; Rest[CoefficientList[InverseSeries[Series[-1 + QPochhammer[x^2]^2/(QPochhammer[x] QPochhammer[x^4]), {x, 0, nmax}], x], x]]

CROSSREFS

Cf. A000700, A007312, A050393, A291489.

Sequence in context: A281635 A180512 A132181 * A027642 A249306 A117214

Adjacent sequences:  A291643 A291644 A291645 * A291647 A291648 A291649

KEYWORD

sign

AUTHOR

Ilya Gutkovskiy, Aug 28 2017

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 18 14:36 EDT 2018. Contains 316321 sequences. (Running on oeis4.)