A290117 Primes of the form k! / 4 - 1.

5, 29, 179, 1259, 10079, 907199, 326918591999, 1600593426431999, 6463004184721244159999

Offset: 1

Author

Robert Price, Jul 19 2017

Keywords

• nonn

Links

• Robert Price, Table of n, a(n) for n = 1..9
• Joe McLean, Interesting Sources of Probable Primes
• OpenPFGW Project, Primality Tester

Crossrefs

Cf. A139174, A139199.

Programs

Mathematica

Select[Table[i! / 4 - 1, {i, 4, 100}], PrimeQ[#]&]

Formula

a(n) = (A139199(n)!-4)/4.