A133982 Numbers n such that 11^n - 2 is prime.

4, 6, 22420, 27636, 27850, 28986, 31168, 586020

Offset

1,1

Comments

Corresponding primes are in A133858.

11^22420-2 is a 23349-digit probable prime found with PrimeForm.

a(8) > 10^5. - Robert Price, Mar 26 2014

a(4) through a(7) also correspond to probable primes. - Robert Price, Mar 27 2014

Links

Table of n, a(n) for n=1..8.

Prog

(PARI) is(n)=ispseudoprime(11^n-2) \\ Charles R Greathouse IV, May 22 2017

Crossrefs

Cf. A133858, A130652.

Sequence in context: A054264 A077305 A146294 * A069179 A336764 A058377

Adjacent sequences: A133979 A133980 A133981 * A133983 A133984 A133985

Keyword

hard,nonn,more

Author

Rick L. Shepherd, Sep 30 2007

Extensions

a(4)-a(7) from Robert Price, Mar 26 2014

a(8) from Paul Bourdelais, Nov 03 2021

Status

approved