A301521 Numbers k such that 4*k^k - 3 is prime.

2, 4, 5, 7, 22, 1045

Offset: 1

Author

Seiichi Manyama, Mar 23 2018

Keywords

• nonn
• hard
• more

Comments

Next term, if it exists, is greater than 5000. - Vaclav Kotesovec, Mar 25 2018

Next term, if it exists, is greater than 25000. - Robert Price, Apr 22 2019

Crossrefs

Cf. A301520, A301870.

Programs

Mathematica

Select[Range[1000], PrimeQ[4*#^# - 3] &] (* Vaclav Kotesovec, Mar 25 2018 *)

PARI

for(n=0, 100, if(isprime(4*n^n-3), print1(n", ")))

Extensions

a(6) from Vaclav Kotesovec, Mar 25 2018