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!)
A052675 E.g.f. (1-x)/(1-5x). 0
1, 4, 40, 600, 12000, 300000, 9000000, 315000000, 12600000000, 567000000000, 28350000000000, 1559250000000000, 93555000000000000, 6081075000000000000, 425675250000000000000, 31925643750000000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..15.

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 623

FORMULA

E.g.f.: (-1+x)/(-1+5*x)

Recurrence: {a(0)=1, (-5*n-5)*a(n)+a(n+1)=0, a(1)=4}

4*5^(n-1)*n!, n>0.

MAPLE

spec := [S, {S=Sequence(Prod(Sequence(Z), Union(Z, Z, Z, Z)))}, labeled]: seq(combstruct[count](spec, size=n), n=0..20);

CROSSREFS

Equals (4/5) * A052562.

Sequence in context: A272261 A291817 A128573 * A141010 A141011 A090359

Adjacent sequences:  A052672 A052673 A052674 * A052676 A052677 A052678

KEYWORD

easy,nonn

AUTHOR

encyclopedia(AT)pommard.inria.fr, Jan 25 2000

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 19 07:24 EDT 2020. Contains 337178 sequences. (Running on oeis4.)