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A143252 Numbers n such that 2*41^n + 1 is prime. 0
0, 1, 819, 1449, 1677, 13319 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Primes found and proved by PrimeForm. No more terms up to 30000.

LINKS

Table of n, a(n) for n=1..6.

PROG

(PARI) is(n)=ispseudoprime(2*41^n+1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A141802.

Sequence in context: A105989 A266059 A020445 * A200565 A212609 A212612

Adjacent sequences:  A143249 A143250 A143251 * A143253 A143254 A143255

KEYWORD

hard,nonn

AUTHOR

Rick L. Shepherd, Aug 02 2008

STATUS

approved

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Last modified August 19 18:51 EDT 2019. Contains 326133 sequences. (Running on oeis4.)