A265502 Numbers n such that n*2^1279 - 1 is prime.

1, 139, 433, 1563, 2095, 2254, 2871, 3751, 4003, 4338, 4843, 6015, 6331, 6933, 7324, 7345, 7485, 7719, 7836, 8070, 8413, 9018, 9840, 9898, 9915, 9931, 10611, 11215, 11356, 11418, 11560, 11740, 12010, 12673, 13039, 13056, 13225, 14136, 14271, 14380, 14974, 15084

Offset: 1

Author

Vardan Semerjyan, Dec 09 2015

Keywords

• nonn

Comments

The exponent of 2 in the expression, 1279, is a Mersenne exponent.

Examples

			n = 1 is a term since 2^1279 - 1 is prime (the 15th Mersenne prime).
		

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A000043, A001348, A005122.

Programs

MATLAB

if isprime(n*2^1279-1)
disp(n)
end

Magma

[n: n in [1..10^4] |IsPrime(n*2^1279-1)]; // Vincenzo Librandi, Dec 10 2015

Mathematica

Select[Range@ 11500, PrimeQ[# 2^1279 - 1] &] (* Michael De Vlieger, Dec 09 2015 *)

PARI

is(n)=ispseudoprime(n*2^1279 - 1) \\ Anders Hellström, Dec 09 2015

Extensions

Terms a(31) and beyond from Andrew Howroyd, Dec 23 2019