0,6

Wilfrid Keller, Prime factors k.2^n + 1 of Fermat numbers F_m

PSI (The algorithm company), Fermat factor status

W. Keller, Summary of factoring status for Fermat numbersF(n)

Eric Weisstein's World of Mathematics, Fermat Number

Cf. A000215.

Sequence in context: A029102 A029081 A005862 this_sequence A029115 A029101 A029080

Adjacent sequences: A046049 A046050 A046051 this_sequence A046053 A046054 A046055

nonn,hard

Eric Weisstein (eric(AT)weisstein.com)

F(12) has 5 known factors with C1187 remaining

F(13) has 4 known factors with C2391 remaining

F(14) has no known factors but is composite.