A050844 Numbers n such that 185*2^n-1 is prime.

2, 6, 10, 18, 26, 40, 46, 78, 230, 542, 1286, 1550, 1728, 2138, 2226, 2686, 3742, 5002, 12730, 42936, 64290, 86602, 86686, 109346, 113966, 133346, 211876, 229850, 238230, 294662, 391322, 459352

Offset

1,1

Links

Table of n, a(n) for n=1..32.

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(185*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A330507 A290220 A320678 * A328960 A282428 A174316

Adjacent sequences: A050841 A050842 A050843 * A050845 A050846 A050847

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