OFFSET
1,1
COMMENTS
Question: Is a(n) > 0 for all n?
a(9) may be equal to 0. - Michel Marcus, May 19 2013
EXAMPLE
4 -> 4^2 + 1 = 17 (prime). So a(4) = 17.
PROG
(PARI) a(n) = {while(! isprime(n), n = n^2 + 1; ); return (n); } \\ Michel Marcus, May 19 2013
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Joseph L. Pe, Jan 08 2004
STATUS
approved