MacTutor
30th June
On this day in 1742, Leonard Euler claimed in a letter to Goldbach that prime numbers of the form 4n+ 1 are represented uniquely as a sum of two squares.
He also mentioned that 641 divides , thereby disproving Fermat's claim that all the so-called numbers Fermat numbers are prime. Years later we have not found another with n > 4 which is prime.
He also mentioned that 641 divides , thereby disproving Fermat's claim that all the so-called numbers Fermat numbers are prime. Years later we have not found another with n > 4 which is prime.