

A058911


Numbers k such that k^k + k + 1 is prime.


3




OFFSET

1,3


COMMENTS

There is no further term up to 10000.  Farideh Firoozbakht, Nov 11 2006


LINKS

Table of n, a(n) for n=1..7.


EXAMPLE

a(2) = 2 because 2^2 + 2 + 1 = 7.


MATHEMATICA

Do[ If[ PrimeQ[ n^n + n + 1], Print[n]], {n, 1, 700} ]


PROG

(PARI) f2(n, k) = for(x=1, n, y=x^x+x+k; if(ispseudoprime(y), print1(x", "))) \\ Cino Hilliard, Jan 07 2005
(PFGW) ABC2 $a^$a + $a + 1
a: from 0 to 1000 // Jinyuan Wang, Mar 01 2020


CROSSREFS

Cf. A058912 (k^k + k  1 is prime).
Sequence in context: A145761 A071714 A077753 * A249247 A276956 A276946
Adjacent sequences: A058908 A058909 A058910 * A058912 A058913 A058914


KEYWORD

nonn,hard,more


AUTHOR

Felice Russo, Jan 10 2001


STATUS

approved



