login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A326887 E.g.f.: Product_{k>=1} (1 + (exp(x)-1)^k/k) / (1 - (exp(x)-1)^k/k). 2

%I #8 Jul 31 2019 12:37:21

%S 1,2,8,48,364,3320,35464,433692,5962548,90931152,1522657264,

%T 27765229844,547487475484,11604952395816,263091290017560,

%U 6351255101776812,162643987129698628,4403250400372110656,125649232950852714496,3769013390615951560068,118555772298034094231724

%N E.g.f.: Product_{k>=1} (1 + (exp(x)-1)^k/k) / (1 - (exp(x)-1)^k/k).

%H Vaclav Kotesovec, <a href="/A326887/b326887.txt">Table of n, a(n) for n = 0..420</a>

%F a(n) = Sum_{k=0..n} A305199(k)*Stirling2(n,k).

%F a(n) ~ n * (n+1)! / (16 * exp(2*gamma) * log(2)^(n+3)), where gamma is the Euler-Mascheroni constant A001620.

%t nmax = 20; CoefficientList[Series[Product[(1+(Exp[x]-1)^k/k)/(1-(Exp[x]-1)^k/k), {k, 1, nmax}], {x, 0, nmax}], x] * Range[0, nmax]!

%Y Cf. A305199, A305986, A305987.

%K nonn

%O 0,2

%A _Vaclav Kotesovec_, Jul 31 2019

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 23 20:14 EDT 2024. Contains 375396 sequences. (Running on oeis4.)