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A323144 Numbers k such that 309*2^k+1 is prime. 1
1, 2, 3, 6, 9, 21, 51, 53, 57, 67, 69, 106, 143, 163, 193, 194, 231, 338, 343, 1197, 1314, 2178, 2266, 3401, 3422, 4751, 5914, 6097, 11403, 16519, 24227, 24447, 27041, 29591, 41466, 44459, 46522, 49458, 55198, 64177, 71877, 79898, 102411, 110503, 113258 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert Price, Table of n, a(n) for n = 1..57

Ray Ballinger, Proth Search Page

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for 300 < k < 600

Y. Gallot, Proth.exe: Windows Program for Finding Large Primes

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

Eric Weisstein's World of Mathematics, Proth Prime

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

MAPLE

select(k->isprime(309*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 05 2019

MATHEMATICA

Select[Range[1000], PrimeQ[309*2^# + 1] &]

CROSSREFS

Sequence in context: A191469 A091053 A095064 * A056353 A111274 A133385

Adjacent sequences:  A323141 A323142 A323143 * A323145 A323146 A323147

KEYWORD

nonn,hard

AUTHOR

Robert Price, Jan 05 2019

STATUS

approved

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Last modified May 26 02:56 EDT 2020. Contains 334613 sequences. (Running on oeis4.)