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A053360 Numbers k such that 287*2^k + 1 is a prime. 0
3, 27, 59, 291, 699, 1259, 1771, 3051, 19379, 23323, 41459, 121747, 206539, 515827 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..14.

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 a prime

MATHEMATICA

Select[Range[5*10^3], PrimeQ[287*2^# + 1] &] (* G. C. Greubel, May 25 2018 *)

PROG

(PARI) is(n)=ispseudoprime(287*2^n+1) \\ G. C. Greubel, May 25 2018

(MAGMA) [n: n in [1..300] | IsPrime(287*2^n+1)];  // G. C. Greubel, May 25 2018

CROSSREFS

Sequence in context: A071183 A025414 A201276 * A176963 A204046 A305094

Adjacent sequences:  A053357 A053358 A053359 * A053361 A053362 A053363

KEYWORD

hard,nonn,more

AUTHOR

N. J. A. Sloane, Dec 29 1999

EXTENSIONS

a(12)-a(14) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 22 2018

STATUS

approved

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Last modified February 27 22:50 EST 2020. Contains 332319 sequences. (Running on oeis4.)