Many US and European math departments host translated problems. For example:
So for (m \ge 1), (m^2 < P(n) < (m+1)^2) ⇒ (P(n)) is consecutive squares ⇒ cannot be a perfect square. russian math olympiad problems and solutions pdf
For students looking for level-appropriate practice rather than the highest-level "federal" stages: Many US and European math departments host translated
Spend at least 30–60 minutes on a single problem before looking at the solution. The growth happens during the struggle, not the reading. not the reading.