Fermat’s Last Theorem

In the margins of his copy of arithmetica, Fermat proposed that the equation xn + yn = zn had no positive integer solutions of x, y and z for n > 2, and claimed to have discovered a proof for this. Yet, to the dismay of mathematicians for centuries to come, he proceeded to write ‘I have a truly marvellous demonstration of this proposition which this margin is too narrow to contain’.

Fermat’s Last Theorem