1,2
Table of n, a(n) for n=1..18.
Steven Harvey, Inverse Carol Primes
2^4 + 2^1 + 1 = 19 is prime so a(1)=1.
2^12 + 2^5 + 1 = 4129 is prime so a(2)=5.
(PARI) is(n)=ispseudoprime(2^(2*(n+1))+2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
(Magma) [k: k in [0..200] | IsPrime(2^(2*(k+1))+2^k+1)]; // Jinyuan Wang, Mar 20 2020
Cf. A105181.
Sequence in context: A149502 A219701 A088974 * A100457 A080872 A328333
Adjacent sequences: A105179 A105180 A105181 * A105183 A105184 A105185
nonn,more
Pierre CAMI, Apr 11 2005
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 05 2008
approved
