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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A022701 Expansion of Product_{m>=1} 1/(1 + m*q^m)^9. 2
1, -9, 27, -30, 72, -387, 738, -801, 2889, -8119, 13005, -25038, 57735, -122643, 247788, -432786, 862497, -1944657, 3520721, -6191280, 12743919, -24916977, 45349101, -83116206, 156731304, -299550636, 547421607 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

FORMULA

G.f.: exp(-9*Sum_{j>=1} Sum_{k>=1} (-1)^(j+1)*k^j*x^(j*k)/j). - Ilya Gutkovskiy, Feb 08 2018

MATHEMATICA

With[{nmax = 50}, CoefficientList[Series[Product[(1 + k*q^k)^-9, {k, 1, nmax}], {q, 0, nmax}], q]] (* G. C. Greubel, Jul 19 2018 *)

PROG

(PARI) m=50; q='q+O('q^m); Vec(prod(n=1, m, (1+n*q^n)^-9)) \\ G. C. Greubel, Jul 19 2018

CROSSREFS

Column k=9 of A297325.

Sequence in context: A255622 A209511 A115148 * A276003 A255343 A108107

Adjacent sequences:  A022698 A022699 A022700 * A022702 A022703 A022704

KEYWORD

sign

AUTHOR

N. J. A. Sloane

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 22 08:42 EDT 2019. Contains 325218 sequences. (Running on oeis4.)