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First occurrence of numbers p such that p = (prime(n)+ prime(n+k))/2 is prime for prime indices n=2, 3, 5... and k=1, 2, ...
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%I #3 Oct 01 2013 17:58:04

%S 5,7,11,139,11,13,449,17,23,83,23,29,331,31,67,53,37,59,41,43,113,53,

%T 509,53,269,59,83,331,67,167,71,173,89,149,83,89,101,223,311,97,101,

%U 283,101,107,113,151,137,131,157,137,127,149,137,271,137,421,197,149,257

%N First occurrence of numbers p such that p = (prime(n)+ prime(n+k))/2 is prime for prime indices n=2, 3, 5... and k=1, 2, ...

%e k=2, prime(2) + prime(2+2) = 10. 10/2 = 5

%e k=3, prime(2) + prime(2+3) = 14. 14/2 = 7

%e k=4, prime(3) + prime(3+4) = 22. 22/2 = 11

%o (PARI)

%K easy,nonn

%O 2,1

%A _Cino Hilliard_, Sep 10 2004