Years ago, I watched a DVD of a musical about a mathematician's struggle to prove Fermat's Last Theorem. I believe it was called "Fermat's Last Tango." It passed through my mind, then and often since, that it would be easy to write a song for a musical on such a theme using the tune to Gilbert and Sullivan's "Modern Major General," a tune designed precisely to allow for complicated exposition. Alas! "Fermat's Last Tango" didn't follow this policy. The tunes like the words were all new. Good for them. But the idea has stuck with me. It has come to this. When squaring A and B and C, it sometimes works out right you see, Both when they push n up to three it never quite goes through: dear me! Now I shall prove just why this stands, and get rewards in Krugerrands. The task involves elliptic curves and forms that they call modul-urves, I'll borrow freely from the guys Who've won each year the Abel Prize. Now: since old Rome...