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A050887
Numbers n such that 257*2^n-1 is prime.
0
4, 6, 10, 16, 24, 60, 66, 82, 184, 256, 324, 424, 632, 756, 814, 872, 1114, 1702, 3282, 3420, 3862, 3864, 4162, 4510, 7030, 8410, 47974, 59236, 61084, 78034, 133980, 194312, 286832, 541402
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OFFSET
1,1
LINKS
Table of n, a(n) for n=1..34.
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
Kosmaj,
Riesel list k<300
.
PROG
(PARI) is(n)=ispseudoprime(257*2^n-1) \\
Charles R Greathouse IV
, Jun 13 2017
CROSSREFS
Sequence in context:
A075637
A027689
A023501
*
A078642
A032416
A283496
Adjacent sequences:
A050884
A050885
A050886
*
A050888
A050889
A050890
KEYWORD
hard
,
nonn
AUTHOR
N. J. A. Sloane
, Dec 29 1999
EXTENSIONS
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
STATUS
approved
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Last modified September 14 09:44 EDT 2024. Contains 375921 sequences. (Running on oeis4.)