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A133982
Numbers n such that 11^n - 2 is prime.
3
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
PROG
(PARI) is(n)=ispseudoprime(11^n-2) \\ Charles R Greathouse IV, May 22 2017
CROSSREFS
Sequence in context: A054264 A077305 A146294 * A069179 A336764 A058377
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