A192611 -id:A192611 - cp's OEIS frontend

A080174 Primes prime(k) such that prime(k)*k falls between twin primes.

3, 113, 359, 827, 2069, 2267, 3643, 5179, 7829, 9029, 10223, 10369, 11777, 18169, 21143, 22409, 23173, 23957, 25411, 28051, 28447, 29251, 31991, 32717, 34487, 38561, 43133, 54323, 57097, 61363, 73043, 82493, 86269, 94099

Offset: 1

Andrea Raffetti, Jul 05 2011

nonn

Also primes p such that pi(p)*p falls between twin primes (see Crossrefs).

			113 is in the list because 113 is the 30th prime and 113*30=3390 falls between the twin primes 3389 and 3391.

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

The sequence is the intersection of A062291 and A192611.
Cf. A000720 pi(n), the number of primes <= n.
Cf. A001359 Lesser of twin primes; A006512 Greater of twin primes.
Cf. A014574 Average of twin prime pairs.

[NthPrime(n): n in [1..10^4] | IsPrime(NthPrime(n)*n-1) and IsPrime(NthPrime(n)*n+1)];  // Bruno Berselli, Jul 06 2011

Prime[Select[Range[10000], PrimeQ[Prime[#]# - 1] && PrimeQ[Prime[#]# + 1] &]] (* Alonso del Arte, Jul 05 2011 *)

v=List();k=0; forprime(p=2, 1e5, if(isprime(k++*p+1)&&isprime(k*p-1),listput(v,p))); Vec(v)

Additional terms from Bruno Berselli, Jul 05 2011

cp's OEIS Frontend

A080174 Primes prime(k) such that prime(k)*k falls between twin primes.

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