OFFSET
1,1
PROG
(PARI) a(n) = {if (n==1, return (2)); p = 3; while(! isprime((prime(n)+p)/2), p = nextprime(p+1)); return (p); } \\ Michel Marcus, Jun 16 2013
CROSSREFS
KEYWORD
easy,nonn,less
AUTHOR
David Wasserman, Jan 03 2005
STATUS
approved