login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A004420 Expansion of (Sum_{n=-inf..inf} x^(n^2))^(-19). 1
1, -38, 760, -10640, 117002, -1075248, 8582224, -61061440, 394559320, -2348001494, 13008061200, -67666510320, 332809029680, -1556541579760, 6955832361824, -29820933412800, 123079426294922, -490508040685920 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Seiichi Manyama, Table of n, a(n) for n = 0..10000

FORMULA

a(n) ~ (-1)^n * exp(Pi*sqrt(m*n)) * m^((m+1)/4) / (2^(3*(m+1)/2) * n^((m+3)/4)), set m = 19 for this sequence. - Vaclav Kotesovec, Aug 18 2015

MATHEMATICA

nmax = 30; CoefficientList[Series[Product[((1 + (-x)^k)/(1 - (-x)^k))^19, {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Aug 18 2015 *)

CROSSREFS

Sequence in context: A162166 A162392 A010990 * A020930 A104761 A270500

Adjacent sequences:  A004417 A004418 A004419 * A004421 A004422 A004423

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 September 26 16:43 EDT 2020. Contains 337374 sequences. (Running on oeis4.)