A301633 Numbers k such that 4^(2*k) + 2*k + 1 is a prime.

0, 1, 33, 123, 235, 513, 3441, 5836

Offset

1,3

Comments

Next term, if it exists, is greater than 10000. - Vaclav Kotesovec, Mar 25 2018

Links

Table of n, a(n) for n=1..8.

Maple

a:=n->`if`(isprime(4^(2*k)+2*k+1), k, NULL): seq(a(k), k=0..5000); # Muniru A Asiru, Mar 25 2018

Mathematica

Flatten[{0, Select[Range[1000], PrimeQ[16^# + 2*# + 1] &]}] (* Vaclav Kotesovec, Mar 25 2018 *)

Prog

(PARI) for(n=0, 500, if(isprime(4^(2*n)+2*n+1), print1(n", ")))

Crossrefs

A301637 gives the primes.

Cf. A173053, A301632.

Sequence in context: A140161 A177211 A337626 * A039440 A235902 A235895

Adjacent sequences: A301630 A301631 A301632 * A301634 A301635 A301636

Keyword

nonn,more

Author

Seiichi Manyama, Mar 25 2018

Extensions

a(7) from Muniru A Asiru, Mar 25 2018

a(8) from Vaclav Kotesovec, Mar 25 2018

Status

approved