Factorial ratios often hide surprising divisibility patterns, and studying when such ratios are integers has attracted recent attention. In this talk, I’ll discuss a variant of this theme involving Euler’s totient function. In particular, we look for the smallest positive integer $c=c(a,b)$ such that $\frac{\varphi(c!)}{\varphi(a!)\cdot\varphi(b!)} \in \mathbb{Z}.$
Talk by Abhishek Jha.