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A032367 Numbers k such that 35*2^k+1 is prime. 1
1, 3, 7, 9, 13, 15, 31, 45, 47, 49, 55, 147, 245, 327, 355, 663, 1423, 1443, 2493, 3627, 4737, 6541, 9667, 22645, 27321, 61963, 68281, 144397, 151741, 187859, 191509, 273251, 494607, 696935, 768063, 831411, 1040005, 1357881, 1765449, 2099769 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..40.

Ray Ballinger, Proth Search Page

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

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

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[35*2^#+1] &] (* Amiram Eldar, Dec 12 2018 *)

PROG

(PARI) is(n)=ispseudoprime(35*2^n+1) \\ Charles R Greathouse IV, Jun 12 2017

(MAGMA) [n: n in [0..5000] | IsPrime(35*2^n+1)]; // Vincenzo Librandi, Dec 12 2018

CROSSREFS

Sequence in context: A309406 A057701 A140291 * A285353 A063204 A236208

Adjacent sequences:  A032364 A032365 A032366 * A032368 A032369 A032370

KEYWORD

nonn,hard

AUTHOR

James R. Buddenhagen

EXTENSIONS

More terms from Hugo Pfoertner, Jun 20 2003

Added more terms (from http://web.archive.org/web/20161028080239/http://www.prothsearch.net/riesel.html), Joerg Arndt, Apr 07 2013

a(40) from http://www.prothsearch.com/riesel1.html by Robert Price, Dec 12 2018

STATUS

approved

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Last modified January 26 08:47 EST 2020. Contains 331278 sequences. (Running on oeis4.)