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A032491 Numbers k such that 229*2^k+1 is prime. 0
6, 82, 186, 334, 690, 838, 1146, 1482, 2262, 5118, 5398, 6294, 9322, 15270, 15930, 28134, 34926, 47878, 52986, 217234, 370086, 484018, 786034, 1118806, 1818078, 1956294 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..26.

Ray Ballinger, Proth Search Page

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300

Wilfrid Keller, List of primes k.2^n - 1 for k < 300

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

MATHEMATICA

Select[Range[1000], PrimeQ[229*2^# + 1] & ] (* Robert Price, Dec 19 2018 *)

PROG

(PARI) is(n)=ispseudoprime(229*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A121790 A279203 A320993 * A135624 A222197 A089397

Adjacent sequences:  A032488 A032489 A032490 * A032492 A032493 A032494

KEYWORD

nonn,hard,more

AUTHOR

N. J. A. Sloane.

EXTENSIONS

a(20)-a(xx26from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 19 2018

STATUS

approved

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Last modified July 15 23:32 EDT 2020. Contains 335774 sequences. (Running on oeis4.)