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!)
A158095 G.f.: A(x) = exp( Sum_{n>=1} 2*sigma(n,n-1)*x^n/n ). 3
1, 2, 5, 14, 61, 370, 3454, 40880, 614346, 10848514, 222870183, 5175100204, 134514302384, 3859406052466, 121274242936381, 4139268759072626, 152532132931199062, 6034430112251517608, 255114747410233804986 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..18.

EXAMPLE

G.f.: A(x) = 1 + 2*x + 5*x^2 + 14*x^3 + 61*x^4 + 370*x^5 +...

PROG

(PARI) a(n)=polcoeff(exp(sum(m=1, n, 2*sigma(m, m-1)*x^m/m)+x*O(x^n)), n)

CROSSREFS

Cf. A023881, A294645.

Sequence in context: A006847 A008286 A049082 * A227365 A059958 A102019

Adjacent sequences:  A158092 A158093 A158094 * A158096 A158097 A158098

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Mar 20 2009

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 20 16:50 EDT 2021. Contains 347586 sequences. (Running on oeis4.)