OFFSET
0,8
COMMENTS
The sequence continues: a(15) = ?, 1, 17753925353, a(18) = ?, 1575, 13, 579, a(22) = ?
LINKS
Fermat factoring status, Prime factors of Fermat numbers
FermatSearch, Home page
Eric Weisstein's World of Mathematics, Fermat Number
CROSSREFS
KEYWORD
nonn,hard
AUTHOR
Arkadiusz Wesolowski, Mar 05 2014
STATUS
approved