Pythagoras triangle the square of the hypotenuse is equal [to the sum of] the squares of the two other sides"—that is, formula_1. According to a popular legend, after he discovered this theorem, Pythagoras sacrificed an ox, or possibly even a whole "hecatomb", to the gods. Cicero rejected this story as spurious because of the much more widely held belief that Pythagoras forbade blood sacrifices. Porphyry attempted to explain the story by asserting that the ox was actually made of dough. The Pythagorean theorem was known and used by the Babylonians and Indians centuries before Pythagoras, but it is possible that he
Proofs of Fermat's theorem on sums of two squares of which is a sum of two squares, is itself a sum of two squares." 2. "If a number which is a sum of two squares is divisible by a prime which is a sum of two squares, then the quotient is a sum of two squares." (This is Euler's first Proposition). 3. "If a number which can be written as a sum of two squares is divisible by a number which is not a sum of two squares, then the quotient has a factor which is not a sum of two squares." (This is Euler's second Proposition). 4. "If