OFFSET
1,1
COMMENTS
There is no further term up to 3000. - Farideh Firoozbakht, Oct 19 2006
a(12) > 20000. - User "Someone", added by Dmitry Petukhov, Sep 09 2021
If it exists, a(12) > 40000. - Dmitry Petukhov, Sep 12 2021
LINKS
User "Someone", Petrov's sequence - probability of distribution of p.h. (in Russian).
MATHEMATICA
Do[ If[ PrimeQ[ n^n - n - 1], Print[n]], {n, 1, 750} ]
PROG
(PARI) is(n)=ispseudoprime(n^n-n-1) \\ Charles R Greathouse IV, May 22 2017
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robert G. Wilson v, Dec 05 2001
EXTENSIONS
a(9)-a(11) from Farideh Firoozbakht, Oct 19 2006
STATUS
approved