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A195190 Primes p such that there is only one prime number between semiprime(p) and semiprime(p+1).

%I A195190 #12 May 13 2013 01:54:20
%S A195190 2,13,23,43,113,151,179,229,233,241,281,283,347,353,359,367,383,401,
%T A195190 431,491,499,503,541,571,593,613,653,677,787,811,827,859,881,967,983,
%U A195190 1051,1093,1117,1223,1237,1259,1277,1279,1289,1303,1409,1433,1453,1471,1493,1499,1511,1531,1549,1607
%N A195190 Primes p such that there is only one prime number between semiprime(p) and semiprime(p+1).
%H A195190 Charles R Greathouse IV, <a href="/A195190/b195190.txt">Table of n, a(n) for n = 1..10000</a>
%e A195190 a(1)=2 because 2 is a prime and semiprime(2)=6<(only one prime 7)<9=semiprime(2+1),
%e A195190 a(2)=13 because 13 is a prime and semiprime(13)=35<(only one prime 37)<38=semiprime(13+1).
%o A195190 (PARI) list(lim)=my(lm=1.1*lim*log(lim)/log(log(lim)),v=List(),u=List(),t);forprime(p=2, sqrt(lm), t=p;forprime(q=p, lm\t, listput(v,t*q))); v=vecsort(Vec(v)); forprime(p=2,lim,t=0;for(k=v[p]+1,v[p+1]-1,if(isprime(k)&&t++>1,break));if(t==1,listput(u,p))); v=0; Vec(u) \\ _Charles R Greathouse IV_, Sep 11 2011
%Y A195190 Gf. A001358.
%K A195190 nonn,less
%O A195190 1,1
%A A195190 _Juri-Stepan Gerasimov_, Sep 11 2011
%E A195190 Sequence corrected by _Charles R Greathouse IV_, Sep 11 2011