OFFSET
1,1
COMMENTS
Run the PARI script savetwins(100000) or so to build the twinprime array of lower bounds before you run the main script.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
Twin prime pairs 17,19 and 29,31 have only the prime 23 between them.
PROG
(PARI) pbetweentw(n, p) = \p is the number of primes between { forstep(x1=1, n, 1, c=0; t1 = twin[x1]; t2 = twin[x1+1]; for(y=t1+4, t2-1, if(isprime(y), c++) ); if(c==p, print1(t1", ")) ) } \ build a twin prime table of lower bounds savetwins(n) = { twin = vector(n); c=1; forprime(x=3, n*10, if(isprime(x+2), twin[c]=x; c++; ) ) }
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Jan 01 2004
EXTENSIONS
Offset corrected by Amiram Eldar, Dec 28 2019
STATUS
approved