Problem of the Week
BUGCAT
Zassenhaus Conference
Hilton Memorial Lecture
BingAWM
Math Club
After 150 years, Euler's conjecture that there is no pair of orthogonal Latin squares of order 6 was proved by Tarry around 1900. The proof was long. Almost a century later, two short proofs were found. I will present one of them, due to Stinson in 1984.