A062538 Primes of the form 4*k! + 1.

5, 97, 20161, 161281, 1451521, 24908083201, 83691159552001, 1219553378446855442006016000001, 923374789356965521888370970732110324333114258287231764529152000000000001

Offset: 1

Author

Jason Earls, Jul 10 2001

Keywords

• nonn

Examples

			4*4! + 1 = 97, a prime.
		

Crossrefs

Cf. A076680, A173322.

Programs

Mathematica

lst={};Do[p=4*n!+1;If[PrimeQ[p],AppendTo[lst,p]],{n,0,5!}];lst (* Vladimir Joseph Stephan Orlovsky, Jan 28 2009 *)
Select[(4Range[60]!+1),PrimeQ] (* Harvey P. Dale, May 08 2024 *)

PARI

for(n=1,55, if(isprime(4*n!+1),print(4*n!+1)))

Formula

a(n) = A173322(A076680(n+1)). - Elmo R. Oliveira, Apr 17 2025