A301641 Primes of form 4*k^k + 1.

5, 17, 109, 3294173, 355271367880050092935562133789062501

Offset: 1

Author

Seiichi Manyama, Mar 25 2018

Keywords

• nonn

Comments

No additional terms through k=1000. - Harvey P. Dale, Oct 06 2023

Crossrefs

Primes of form b*k^k + 1: A121270 (b=1), A216148 (b=2), A301644 (b=3), this sequence (b=4), A301642 (b=16).

Cf. A301519, A301808.

Programs

Maple

a:=k->`if`(isprime(4*k^k+1),4*k^k+1,NULL): seq(a(k),k=1..1400); # Muniru A Asiru, Mar 25 2018

Mathematica

Select[Table[4n^n+1,{n,30}],PrimeQ] (* Harvey P. Dale, Oct 06 2023 *)

Formula

a(n) = 4*A301519(n+1)^A301519(n+1) + 1.