Question 15
How many primes $p$ make $p+81$ a perfect square?
HKIMO 2026 THPT (Grades 10–12 shared) National Preliminary Set 02 Question 15
HKIMO · HKIMO 2026 THPT (Grades 10–12 shared) National Preliminary Set 02
HKIMO · HKIMO 2026 THPT (Grades 10–12 shared) National Preliminary Set 02