A063791 Numbers k such that 2^(k+1) - k - 2 is prime.

3, 9, 13, 15, 25, 49, 55, 69, 115, 2071, 6249, 13669, 14215, 14625, 396127

Offset: 1

Author

Jason Earls, Aug 17 2001

Keywords

• nonn
• more

References

• Dean Hickerson, personal communication.

Crossrefs

Cf. A099439.

Programs

PARI

for(n=1,5000, if(isprime(2^(n+1)-n-2),print(n)))

Formula

a(n) = A099439(n) - 1. - Hugo Pfoertner, Jul 24 2019

Extensions

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008

a(15) from Karsten Bonath, Jun 07 2018