OFFSET
1,1
COMMENTS
Also primes of the form 2^(2k+1)-3, since 2^n-3 == 2 (mod 3) iff n is odd. - Robert Israel, Feb 17 2016
LINKS
Robert Israel, Table of n, a(n) for n = 1..11
MAPLE
map(t -> 2^t-3, select(t -> isprime(2^t-3), [seq(t, t=1..2000, 2)])); # Robert Israel, Feb 17 2016
MATHEMATICA
Flatten[Table[If[IntegerQ[Rationalize[N[ (1 + 2^n)/ 3]]] && PrimeQ[2^n - 3], 2^n - 3, {}], {n, 2, 100000}]]
PROG
(Magma) [2^n-3: n in [1..300] | IsPrime(2^n-3) and (2^n-3) mod 3 eq 2] - Jaroslav Krizek, Feb 17 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Apr 23 2010
EXTENSIONS
Definition corrected by Jaroslav Krizek, Feb 17 2016
a(5)-a(7) from Jaroslav Krizek, Feb 17 2016
STATUS
approved