Euler's Sum of Powers Conjecture

Famous False Conjecture

No $n$th power can be the sum of fewer than $n$ $n$th powers.

$144^5 = 27^5 + 84^5 + 110^5 + 133^5$

This entry was named for Leonhard Paul Euler.

This was proven false by the counterexample found by Leon J. Lander and Thomas R. Parkin in $1966$, when they were using a computer to hunt for $5$th powers which were the sum of $5$ $5$th powers.

In one of the $4$ solutions they found, one of the contributing $5$th powers was $0^5$.

It was at that point it was realised that here was a counterexample to Euler's Sum of Powers Conjecture.

Since then, further counterexamples have been found, for various powers.