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A236687 Primes p such that prime(p^2) - 2 is also prime.

%I A236687 #11 Jan 30 2014 10:37:34
%S A236687 2,11,17,47,61,137,163,229,239,263,317,389,419,449,467,557,571,617,
%T A236687 619,653,709,937,953,1009,1033,1087,1123,1129,1181,1249,1481,1831,
%U A236687 1987,2003,2099,2207,2381,2441,2579,2663,2707,3109,3457,3833,4013,4463,4519,4783
%N A236687 Primes p such that prime(p^2) - 2 is also prime.
%H A236687 K. D. Bajpai, <a href="/A236687/b236687.txt">Table of n, a(n) for n = 1..564</a>
%e A236687 17 is prime and appears in the sequence because prime(17^2) = 1879 and 1879 - 2 = 1877, which is also prime.
%e A236687 47 is prime and appears in the sequence because prime(47^2) = 19471 and 19471 - 2 = 19469, which is also prime.
%p A236687 KD := proc() local a,b,d; a:=ithprime(n); b:=ithprime(a^2)-2; if isprime (b) then RETURN (a);fi; end: seq(KD(), n=1..500);
%o A236687 (PARI)
%o A236687 default(primelimit,2^31)
%o A236687 s=[]; forprime(p=2, 5000, if(isprime(prime(p^2)-2), s=concat(s, p))); s \\ _Colin Barker_, Jan 30 2014
%Y A236687 Cf. A000040, A234695, A236119.
%K A236687 nonn
%O A236687 1,1
%A A236687 _K. D. Bajpai_, Jan 29 2014