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%I #10 Sep 06 2016 03:04:11
%S 1,2,5,10
%N Numbers n such that 2^n+9 and 2^n+27 are prime.
%C No further terms between 10 and 5000. - _R. J. Mathar_, Feb 07 2010
%C No further terms to 100000. Expected number of remaining terms: (zeta(2) - 1 - 1/4 - ... - 1/100000^2)/log^2 2 ~= 0.00002. - _Charles R Greathouse IV_, Mar 25 2010
%F A057196 INTERSECT A157007 - _R. J. Mathar_, Feb 07 2010
%e a(1)=1 because 2^1+3^2=11 and 2^1+3^3=29 are prime.
%t Select[Range[10],AllTrue[2^#+{9,27},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, May 28 2016 *)
%o (PARI) is(n)=isprime(2^n+9) && isprime(2^n+27) \\ _Charles R Greathouse IV_, Sep 06 2016
%K nonn,less
%O 1,2
%A _Juri-Stepan Gerasimov_, Feb 02 2010
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