OFFSET
1,1
COMMENTS
Also primes p such that pi(p)*p falls between twin primes (see Crossrefs).
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
EXAMPLE
113 is in the list because 113 is the 30th prime and 113*30=3390 falls between the twin primes 3389 and 3391.
MATHEMATICA
Prime[Select[Range[10000], PrimeQ[Prime[#]# - 1] && PrimeQ[Prime[#]# + 1] &]] (* Alonso del Arte, Jul 05 2011 *)
PROG
(PARI) v=List(); k=0; forprime(p=2, 1e5, if(isprime(k++*p+1)&&isprime(k*p-1), listput(v, p))); Vec(v)
(Magma) [NthPrime(n): n in [1..10^4] | IsPrime(NthPrime(n)*n-1) and IsPrime(NthPrime(n)*n+1)]; // Bruno Berselli, Jul 06 2011
KEYWORD
nonn
AUTHOR
Andrea Raffetti, Jul 05 2011
EXTENSIONS
Additional terms from Bruno Berselli, Jul 05 2011
STATUS
approved