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A050840 Numbers n such that 177*2^n-1 is prime. 0
1, 12, 13, 24, 25, 34, 36, 48, 61, 66, 196, 264, 376, 672, 732, 877, 1032, 1104, 1177, 1242, 2664, 7756, 35034, 37728, 57796, 96978, 98353, 277458, 282546, 418816, 582454, 653686, 663601, 665874, 668682, 769026 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..36.

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(177*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A035123 A140212 A123132 * A118068 A108710 A108709

Adjacent sequences:  A050837 A050838 A050839 * A050841 A050842 A050843

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 13 00:17 EST 2017. Contains 295954 sequences.