A065798 Numbers k such that k^k - k - 1 is prime.

3, 4, 5, 6, 9, 17, 22, 85, 710, 844, 1379

Offset: 1

Author

Robert G. Wilson v, Dec 05 2001

Keywords

• nonn
• more

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).

Crossrefs

Cf. A058912 (k^k+k-1).

Programs

Mathematica

Do[ If[ PrimeQ[ n^n - n - 1], Print[n]], {n, 1, 750} ]

PARI

is(n)=ispseudoprime(n^n-n-1) \\ Charles R Greathouse IV, May 22 2017

Extensions

a(9)-a(11) from Farideh Firoozbakht, Oct 19 2006