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Primes which can be written as prime(prime(k))-6 for some k>1.
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%I #11 Oct 01 2013 17:57:59

%S 5,11,53,61,103,151,173,271,277,347,503,541,557,593,733,853,1291,1427,

%T 1493,1663,1907,2411,2543,2677,2713,2797,2903,3061,3163,3253,3313,

%U 3463,3511,3631,3727,4021,4127,4211,4391,4457,4561,4657,4871,4937,5101,5743

%N Primes which can be written as prime(prime(k))-6 for some k>1.

%e Prime(17) = 59, 59 - 6 = 53 is a prime, thus 53 is in the sequence.

%t Select[Prime[Prime[Range[2, 134]]] - 6, PrimeQ[#] &] (* _Giovanni Resta_, Oct 20 2012 *)

%o (PARI) a(n) = { forprime(x=2,n, y=prime(x)- 6; if(isprime(y),print1(y",")) ) }

%K nonn

%O 1,1

%A _Cino Hilliard_, May 31 2004