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A269834
Primes p of the form 2^k + 9*(-1)^k - 8.
0
2, 5, 17, 257, 65537
OFFSET
1,1
COMMENTS
Union of number 2 and Fermat primes > 3 from A019434; for odd k, the numbers 2^k - 17 are divisible by 3.
Also primes p of the form 2^k + 12*(-1)^k - 11 for k >= 0 because for odd k, the numbers 2^k - 23 are divisible by 3.
Also primes p of the form 2^k + 1/2*(q + 1)*(-1)^k - 1/2*(q - 1) for k >= 0 where q = prime of the form 3m - 1 > 29 from A003627 because for odd k, the numbers 2^k - q are divisible by 3.
Corresponding values of k: 0, 2, 4, 8, 16, ...
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.
Sequence in context: A067339 A096848 A283107 * A290200 A132198 A269835
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Mar 06 2016
STATUS
approved