A032453 Numbers k such that 153*2^k+1 is prime.

1, 2, 13, 16, 17, 26, 37, 62, 73, 97, 112, 286, 313, 317, 1001, 1237, 1565, 2665, 5753, 9232, 13202, 14665, 15226, 16633, 50237, 82205, 122821, 181093, 402206, 801973, 877553, 1214002, 2079401, 2697173

Offset

1,2

Links

Table of n, a(n) for n=1..34.

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[153*2^# + 1] & ] (* Robert Price, Dec 18 2018 *)

Prog

(PARI) is(n)=ispseudoprime(153*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A042253 A041645 A318999 * A298295 A257636 A258317

Adjacent sequences: A032450 A032451 A032452 * A032454 A032455 A032456

Keyword

nonn,hard,more

Author

N. J. A. Sloane.

Extensions

a(28)-a(32) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 18 2018

a(33)-a(34) from Jeppe Stig Nielsen, Mar 12 2020

Status

approved