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A050599 Numbers n such that 147*2^n-1 is prime. 0
1, 2, 4, 5, 12, 25, 33, 40, 44, 53, 60, 74, 92, 133, 177, 397, 453, 669, 977, 2226, 2612, 3230, 3314, 5001, 5333, 5376, 7384, 7924, 10265, 18349, 19554, 21854, 30426, 33533, 49280, 70530, 92445, 105789, 177017, 198692, 212496, 464300 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..42.

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(147*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A056984 A117556 A091071 * A281643 A102932 A128457

Adjacent sequences:  A050596 A050597 A050598 * A050600 A050601 A050602

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 October 19 07:15 EDT 2021. Contains 348074 sequences. (Running on oeis4.)