RagvaloD wrote: $\alpha,\beta$ are positive irrational numbers and $[\alpha[\beta x]]=[\beta[\alpha x]]$ for every positive $x$. Prove that $\alpha=\beta$ It was here. Please use the search function.

^He's posting them to make a contest collection of St Petersburg problems.

Kayak wrote: ^He's posting them to make a contest collection of St Petersburg problems. No reason to repost them, obviously.