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Primes of form 2^j + 17^j.
2

%I #9 Oct 15 2013 22:32:23

%S 2,19,293,83537

%N Primes of form 2^j + 17^j.

%C The number j must be zero or a power of 2. Checked j being powers of two through 2^20. Thus a(5) > 10^2500000. Primes of this magnitude are rare (about 1 in 5.9 million), so chance of finding one is remote with today's computer algorithms and speeds. - _Robert Price_, Apr 29 2013

%e j=0: p=1+1=2;j=1: p=2+17=19;j=2: p=4+289=293;j=4: p=16+83521=83537; the j exponents are powers of 2.

%t Select[Table[2^n+17^n,{n,0,2000}],PrimeQ] (* _Harvey P. Dale_, Nov 27 2012 *)

%Y Cf. A082101, A094473-A094480.

%K nonn

%O 1,1

%A _Labos Elemer_, Jun 01 2004