User contributions
- 15:57, 28 February 2021 (diff | hist) . . (+1) . . 2020 USOMO Problems/Problem 3 (current)
- 15:53, 28 February 2021 (diff | hist) . . (+310) . . N 2020 USOMO Problems/Problem 3 (Created page with "Let p be an odd prime. An integer x is called a quadratic non-residue if p does not divide x − t^2 for any integer t. Denote by A the set of all integers a such that 1 ≤ a...")
