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!)
A081713 n! - n# - 1 is prime, where n# is the primorial function. 3

%I #9 Nov 15 2019 16:04:37

%S 4,5,20,92,106,266,308,343,583,597,903,1021,1239,1314,2458,6160,9627,

%T 10649

%N n! - n# - 1 is prime, where n# is the primorial function.

%C Some of the larger entries may only correspond to probable primes.

%H Mike Oakes, <a href="http://groups.yahoo.com/group/primenumbers/message/12028">Primo-factorials</a>.

%H Mike Oakes, <a href="/A081710/a081710.txt">Primo-factorials</a>, message 12028 in primenumbers Yahoo group, Apr 3, 2003. [Cached copy]

%H Joe McLean, <a href="http://web.archive.org/web/20091027034731/http://uk.geocities.com/nassarawa%40btinternet.com/probprim2.htm">Interesting Sources of Probable Primes</a>.

%e a(1)=4 because 4!-4#-1=17 is prime

%Y Cf. A081710, A081711, A081712.

%K nonn,more,hard

%O 1,1

%A _Mike Oakes_, Apr 04 2003

%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008

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 April 23 08:19 EDT 2024. Contains 371905 sequences. (Running on oeis4.)