A050557 - OEIS

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A050557

Numbers n such that 63*2^n-1 is prime.

0

2, 3, 8, 11, 14, 16, 28, 32, 39, 66, 68, 91, 98, 116, 126, 164, 191, 298, 323, 443, 714, 758, 759, 1059, 1168, 1511, 1792, 2116, 3148, 3836, 4084, 4622, 6164, 9268, 10062, 14623, 15799, 23634, 44198, 53971, 55244, 81519, 99411, 112554, 114906, 123774, 132203, 155998, 218694, 323432, 340463

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

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(63*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A293910 A173269 A364217 * A039000 A059671 A212771

Adjacent sequences: A050554 A050555 A050556 * A050558 A050559 A050560

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