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A053358 Numbers k such that 283*2^k + 1 is prime. 0
30, 264, 486, 1950, 3480, 14106, 77394, 472530, 1494614, 2868750 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..10.

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[5*10^3], PrimeQ[283*2^# + 1] &] (* G. C. Greubel, May 24 2018 *)

PROG

(PARI) is(n)=ispseudoprime(283*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017

(MAGMA) [n: n in [1..5000] | IsPrime(283*2^n+1)];  // G. C. Greubel, May 24 2018

CROSSREFS

Sequence in context: A126525 A230615 A230731 * A163667 A214944 A259455

Adjacent sequences:  A053355 A053356 A053357 * A053359 A053360 A053361

KEYWORD

hard,nonn,more

AUTHOR

N. J. A. Sloane, Dec 29 1999

EXTENSIONS

a(8)-a(9) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 20 2018

a(10) from Jeppe Stig Nielsen, Jan 19 2020

STATUS

approved

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Last modified March 7 14:00 EST 2021. Contains 341886 sequences. (Running on oeis4.)