OFFSET
1,1
COMMENTS
Distance from 4m^2+1 to 4n^2+1 is measured as n-m.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..26
PROG
(PARI) r=0; last=2; forstep(n=4, 1e9, 2, if(!ispseudoprime(n^2+1), next); if(n-last>r, r=n-last; print1(last^2+1", ")); last=n) \\ Charles R Greathouse IV, Apr 09 2013
CROSSREFS
KEYWORD
nonn,hard
AUTHOR
T. D. Noe, Aug 14 2012
EXTENSIONS
a(19)-a(21) from Charles R Greathouse IV, Apr 09 2013
STATUS
approved