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A032486 Numbers k such that 219*2^k+1 is prime. 1
1, 2, 3, 9, 13, 14, 17, 21, 22, 25, 27, 51, 58, 99, 138, 197, 325, 386, 413, 475, 529, 771, 826, 1114, 1981, 2249, 2333, 2673, 3171, 3534, 5214, 7197, 7275, 9307, 16321, 16851, 17993, 18753, 19825, 26165, 27477, 27997, 33253, 64537, 64694, 71259, 134666 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Jeppe Stig Nielsen, Table of n, a(n) for n = 1..59 (terms n = 1..58 from Robert Price)

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[219*2^# + 1] & ] (* Robert Price, Dec 19 2018 *)

PROG

(PARI) is(n)=ispseudoprime(219*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A047162 A155929 A175206 * A123859 A048744 A101234

Adjacent sequences:  A032483 A032484 A032485 * A032487 A032488 A032489

KEYWORD

nonn,hard

AUTHOR

N. J. A. Sloane.

EXTENSIONS

a(47)-a(58) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 19 2018

STATUS

approved

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Last modified July 8 00:40 EDT 2020. Contains 335502 sequences. (Running on oeis4.)