Diophantine equations are equations that are solved in integer numbers. We can solve some diophantine equations by factoring in one side of the equation.
Problem (42PMO, 2019)
Three prime numbers are such that their product is 103 times greater than their sum. Find all such numbers.
Solution
Answer: the only such numbers are 3, 53, and 103.
Let the numbers be
Notice that
Train for Math Olympiads
Learn moreWe will solve this diophantine equation by factorization:
Let us consider the following cases for the factorization of
It is not hard to see that the only pairs that represent two primes are