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%I #14 Dec 19 2014 17:56:59
%S 2,23,97,163,463,491,557,659,677,977,1033,1151,1187,1429,1439,1511,
%T 1579,1663,1933,2111,2113,2141,2381,2969,3301,3491,3803,3929,4201,
%U 4421,4447,4513,4547,4789,5039,5273,5281,5303,5309,5449,5669,5741,5939,5981,6053
%N Primes p such that prime(prime(p^2)) + 2 is also prime.
%H K. D. Bajpai, <a href="/A238185/b238185.txt">Table of n, a(n) for n = 1..163</a>
%e 23 is in the sequence because 23 is prime and prime(prime(23^2)) + 2 = 35803 is also prime.
%e 97 is in the sequence because 97 is prime and prime(prime(97^2)) + 2 = 1269643 is also prime.
%p KD := proc() local a,b,d; a:=ithprime(n); b:=ithprime(ithprime(a^2))+2; if isprime (b) then RETURN (a);fi; end: seq(KD(), n=1..300);
%t n=0; Do[If[PrimeQ[Prime[Prime[Prime[k]^2]]+2],n=n+1; Print[n," ",Prime[k]]], {k,1,5000}]
%t Select[Prime[Range[800]],PrimeQ[Prime[Prime[#^2]]+2]&] (* _Harvey P. Dale_, Dec 19 2014 *)
%Y Cf. A000040, A234695, A236119, A236687, A236688, A237283.
%K nonn,less
%O 1,1
%A _K. D. Bajpai_, Feb 19 2014
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