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!)
A072118 a(n) = (2*n)!/core(n!)^2/(n+1) where core(x) is the squarefree part of x. 0
1, 2, 5, 224, 672, 2737152, 8895744, 474439680, 130660687872, 4513732853760000, 15798064988160000, 894413525483520000, 3194334019584000000, 27610545531676262400000, 8107146431738442547200000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
PROG
(PARI) for(n=1, 50, print1((2*n)!/core(n!)^2/(n+1), ", "))
CROSSREFS
Sequence in context: A096695 A084297 A041873 * A249180 A135724 A137068
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Jun 19 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 29 10:22 EDT 2024. Contains 371268 sequences. (Running on oeis4.)