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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
OFFSET
1,2
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
KEYWORD
nonn,hard
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