A108062 Numbers n such that 2^(2n-1) + 2^n + 1 is prime.

1, 2, 3, 6, 10, 15, 79, 82, 142, 190, 499, 5071, 7350

Offset

1,2

Comments

Next term >= 10^4. - Jeppe Stig Nielsen, Mar 28 2014

Links

Table of n, a(n) for n=1..13.

Jacques Basaldua, All Fermat and Mersenne numbers are squarefree.. [link broken]

Formula

A006599(n) = a(n) - 1.

Mathematica

Do[ If[ PrimeQ[2^(2n - 1) + 2^n + 1], Print[n]], {n, 5500}] (* Robert G. Wilson v, Jun 03 2005 *)

Prog

(PARI) is(n)=ispseudoprime(2^(2*n-1)+2^n+1) \\ Charles R Greathouse IV, Jun 12 2017

Crossrefs

Cf. A138576.

Sequence in context: A238891 A048681 A051891 * A347117 A269403 A075623

Adjacent sequences: A108059 A108060 A108061 * A108063 A108064 A108065

Keyword

base,nonn

Author

Alexandre Wajnberg, Jun 02 2005

Extensions

a(1) and a(12) from Robert G. Wilson v, Jun 03 2005

a(13) = 7350 from Jeppe Stig Nielsen, Mar 28 2014

Status

approved