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A050563 Numbers n such that 75*2^n-1 is prime. 0
1, 3, 5, 6, 18, 19, 20, 22, 28, 29, 39, 43, 49, 75, 85, 92, 111, 126, 136, 159, 162, 237, 349, 381, 767, 969, 1247, 1893, 1951, 2363, 2657, 3065, 3090, 3836, 4110, 4342, 5671, 6807, 21945, 24658, 30082, 31811, 54510, 70828, 79292, 80938, 84432, 92235, 113429, 170933, 182433, 196071, 199819, 231580, 306789, 424392, 434323 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..57.

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.

CROSSREFS

Sequence in context: A227963 A099678 A192119 * A168156 A272440 A276704

Adjacent sequences:  A050560 A050561 A050562 * A050564 A050565 A050566

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 December 7 07:15 EST 2016. Contains 278841 sequences.