A269834 Primes p of the form 2^n + 9*(-1)^n - 8.

2, 5, 17, 257, 65537

Offset

1,1

Comments

Union of number 2 and Fermat primes > 3 from A019434; for odd n, numbers 2^n - 17 are divisible by 3.

Also primes p of the form 2^n + 12*(-1)^n - 11 for n >= 0 because for odd n, numbers 2^n - 23 are divisible by 3.

Also primes p of the form 2^n + 1/2*(q + 1)*(-1)^n - 1/2*(q - 1) for n >= 0 where q = prime of the form 3m - 1 > 29 from A003627 because for odd n, numbers 2^n - q are divisible by 3.

Corresponding values of n: 0, 2, 4, 8, 16, ...

Links

Table of n, a(n) for n=1..5.

Prog

(Magma) [2^n + 9*(-1)^n - 8: n in [0..1000] | IsPrime(2^n + 9*(-1)^n - 8)]

Crossrefs

Sequence is different from A132198 and A111635.

Cf. A003627, A019434.

Sequence in context: A067339 A096848 A283107 * A290200 A132198 A269835

Adjacent sequences: A269831 A269832 A269833 * A269835 A269836 A269837

Keyword

nonn

Author

Jaroslav Krizek, Mar 06 2016

Status

approved