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Odd isolated primes.
4

%I #7 Mar 11 2014 01:34:10

%S 23,37,47,53,67,79,83,89,97,113,127,131,157,163,167,173,211,223,233,

%T 251,257,263,277,293,307,317,331,337,353,359,367,373,379,383,389,397,

%U 401,409,439,443,449,457,467,479,487,491,499,503,509,541,547,557,563,577

%N Odd isolated primes.

%H Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos</a>.

%F a(n) = A007510(n+1).

%F a(n) ~ n log n. - _Charles R Greathouse IV_, Jun 07 2013

%t Flatten[Select[Split[Prime[Range[106]], #2 - #1 < 4 &], Length[#] == 1 &]] (* _Jayanta Basu_, Jun 07 2013 *)

%o (PARI) select(p->!isprime(p-2)&&!isprime(p+2),primes(100)[2..100]) \\ _Charles R Greathouse IV_, Jun 07 2013

%K easy,nonn,less

%O 1,1

%A _Omar E. Pol_, Nov 14 2007