Question 99
Find all triples of pairwise distinct positive integers $(a, b, c)$ that satisfy the condition: number $2a-1$ is divisible by $b$, number $2b-1$ is divisible by $c$ and number $2c-1$ is divisible by $a$.
Math Olympiad Vault · MathNet 2018-part-06 — 181 problems (EN–VI)