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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A074728 a(n) = Sum_{k=1..n} k^(n-k)*binomial(n,k-1). 1
1, 3, 10, 39, 176, 903, 5174, 32623, 223792, 1655463, 13110758, 110510007, 986490272, 9287036671, 91872460702, 952034494431, 10305790066208, 116254839687543, 1363631057783942, 16599343732844455, 209328335818064176, 2730323984395924623, 36780442970179975646 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..23.

FORMULA

E.g.f.: (exp(x*exp(x))-exp(x))/x.

MATHEMATICA

Table[Sum[k^(n-k) Binomial[n, k-1], {k, n}], {n, 30}] (* Harvey P. Dale, Mar 19 2013 *)

CROSSREFS

Cf. A000248.

Sequence in context: A137590 A124532 A305560 * A087860 A307593 A221973

Adjacent sequences:  A074725 A074726 A074727 * A074729 A074730 A074731

KEYWORD

nonn

AUTHOR

Vladeta Jovovic, Sep 05 2002

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 02:20 EDT 2019. Contains 325210 sequences. (Running on oeis4.)