login
A143252
Numbers n such that 2*41^n + 1 is prime.
0
0, 1, 819, 1449, 1677, 13319
OFFSET
1,3
COMMENTS
Primes found and proved by PrimeForm. No more terms up to 30000.
PROG
(PARI) is(n)=ispseudoprime(2*41^n+1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Cf. A141802.
Sequence in context: A356414 A020445 A356416 * A200565 A212609 A212612
KEYWORD
hard,nonn
AUTHOR
Rick L. Shepherd, Aug 02 2008
STATUS
approved