A289855 Primes of the form k!2-128, where k!2 is the double factorial number (A006852).

10267, 135007, 13749310447, 1192568192774434123539907640497, 29215606371473169285018060091249259296747, 1009847364737869270905302433221592504062302663202724609247, 34720596058582394465875230149026168047833371128291024141249287753332469144201839599609247

Offset

1,1

Links

Robert Price, Table of n, a(n) for n = 1..10

Henri & Renaud Lifchitz, PRP Records.Search for n!2-128.

Joe McLean, Interesting Sources of Probable Primes

OpenPFGW Project, Primality Tester

Mathematica

MultiFactorial[n_, k_] := If[n<1, 1, n*MultiFactorial[n-k, k]];
Select[Table[MultiFactorial[i, 2] - 128, {i, 8, 100}], PrimeQ[#]&]
Select[Range[8, 120]!!-128, PrimeQ] (* Harvey P. Dale, Dec 01 2018 *)

Crossrefs

Cf. A257864.

Sequence in context: A252031 A356979 A187311 * A204691 A270762 A200712

Adjacent sequences: A289852 A289853 A289854 * A289856 A289857 A289858

Keyword

nonn

Author

Robert Price, Jul 13 2017

Status

approved