A Fermat number, named after Pierre de Fermat, is a number of the form: \(F_{n} = 2^{2^{ \overset{n} {}}} + 1\) It was originally conjectured that all Fermat numbers were prime, but this has been proven false; in fact, only the first five Fermat numbers (F0 to F4) are known to be prime. F334 is the first Fermat number that is larger than a googolplex. The largest Fermat number which is known to be composite, as of February 2015, is F3329782.