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A050598 Numbers n such that 145*2^n-1 is prime. 0
5, 13, 15, 31, 77, 151, 181, 245, 445, 447, 883, 1037, 3557, 43733, 290861, 464887, 530181 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..17.

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(145*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A230503 A335695 A067696 * A297862 A298129 A158334

Adjacent sequences:  A050595 A050596 A050597 * A050599 A050600 A050601

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 19 12:10 EDT 2021. Contains 347556 sequences. (Running on oeis4.)