Problem: Solve the equation for positive integers x, y.
Adding 1 to both sides and adjusting we get
We have two cases :
Case 1: implying
This is an easy check (plug in 1, 2, … , 10).
We find works.
Case 2: implying
Then y is at least x+1.
But this implies
But x is a positive integer. Hence this is not possible.
- Paper: RMO 2015 (Chennai)
- What is this topic: Number Theory
- What are some of the associated concepts: Diophantine Equation
- Where can learn these topics: Cheenta I.S.I. & C.M.I. course,Cheenta Math Olympiad Program, discuss these topics in the ‘Number Theory’ module.
- Book Suggestions: Theory of Numbers by Sierpinsky