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Primes p such that prime(prime(p^2)) - 2 is also prime.
1

%I #11 Feb 11 2014 16:48:35

%S 13,17,167,179,211,223,337,373,541,661,743,751,1063,1129,1217,1607,

%T 1697,1741,1913,2017,2039,2083,2293,2389,2447,2459,2543,2677,2693,

%U 2711,2851,2909,3083,3191,3209,3259,3571,3889,3917

%N Primes p such that prime(prime(p^2)) - 2 is also prime.

%H K. D. Bajpai, <a href="/A237423/b237423.txt">Table of n, a(n) for n = 1..155</a>

%e 13 is prime and appears in the sequence because prime(prime(13^2)) - 2 = 8009 which is also prime.

%e 17 is prime and appears in the sequence because prime(prime(17^2)) - 2 = 16139 which is also prime.

%p KD := proc() local a,b; a:=ithprime(n); b:=ithprime(ithprime(a^2))-2; if isprime (b) then RETURN (a); fi; end: seq(KD(), n=1..500);

%t p[n_] := PrimeQ[Prime[Prime[n^2]] - 2]; n = 0; Do[If[p[Prime[m]], n = n + 1; Print[n, " ", Prime[m]]], {m, 1000}] (* Bajpai *)

%t Select[Prime[Range[105]], PrimeQ[Prime[Prime[#^2]] - 2] &] (* _Wouter Meeussen_, Feb 09 2014 *)

%Y Cf. A000040, A234695, A236119, A236687, A236688, A237283

%K nonn,base,less

%O 1,1

%A _K. D. Bajpai_, Feb 07 2014