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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A131491 2*prime(n)!. 0
4, 12, 240, 10080, 79833600, 12454041600, 711374856192000, 243290200817664000, 51704033477769953280000, 17683523987479403909087232000000, 16445677308355845635451125760000000, 27527506182452690092631959163161804800000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..12.

FORMULA

a(n) = 2*A039716(n) = 2*A000142[A000040(n)]. - R. J. Mathar, Jul 31 2007

MATHEMATICA

2*Prime[Range[15]]! (* Harvey P. Dale, Dec 19 2011 *)

CROSSREFS

Sequence in context: A175718 A076030 A202859 * A286881 A291098 A009506

Adjacent sequences:  A131488 A131489 A131490 * A131492 A131493 A131494

KEYWORD

easy,nonn

AUTHOR

Giovanni Teofilatto, Jul 29 2007

EXTENSIONS

More terms from Harvey P. Dale, Dec 19 2011

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 December 11 21:21 EST 2019. Contains 329937 sequences. (Running on oeis4.)