A288406 Primes of the form k!2+8, where k!2 is the double factorial number (A006852).

11, 23, 113, 953, 2027033, 34459433, 7905853580633, 13113070457687988603440633, 112275575285571389562324404930670903477890633, 79777941814291672401518892224505807820921910393015244140633

Offset: 1

Author

Robert Price, Jun 08 2017

Keywords

• nonn

Links

• Robert Price, Table of n, a(n) for n = 1..12
• Henri& Renaud Lifchitz, PRP Records.Search for n!2+8.
• Joe McLean, Interesting Sources of Probable Primes
• OpenPFGW Project, Primality Tester

Crossrefs

Cf. A076188.

Programs

Mathematica

MultiFactorial[n_, k_] := If[n<1, 1, n*MultiFactorial[n-k, k]];
Select[Table[MultiFactorial[i, 2] + 8, {i, 0, 100}], PrimeQ[#]&]
Select[Range[100]!!+8,PrimeQ] (* Harvey P. Dale, May 05 2019 *)