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!)
A256509 a(n) = (n!)! - n! - 1. 1
-1, -1, -1, 713, 620448401733239439359975 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Term a(5) has 199 decimal digits. - Michael De Vlieger, Mar 31 2015

LINKS

Table of n, a(n) for n=0..4.

EXAMPLE

a(3) = (3!)! - 3! - 1 = 720 - 6 - 1 = 713.

MATHEMATICA

Table[(n!)! - n! - 1, {n, 0, 5}] (* Michael De Vlieger, Mar 31 2015 *)

CROSSREFS

Sequence in context: A269060 A265142 A251031 * A259674 A321493 A260282

Adjacent sequences:  A256506 A256507 A256508 * A256510 A256511 A256512

KEYWORD

sign

AUTHOR

Assoul Abdelkarim, Mar 31 2015

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 15 20:00 EST 2019. Contains 330000 sequences. (Running on oeis4.)