Diophantine Reciprocals
September 19, 2014
Career Cup claims that Amazon asked this as an interview question; it is also Problem 108 at Project Euler:
In the following equation x, y and n are positive integers: 1 / x + 1 y = 1 / n. For n = 4 there are exactly three distinct solutions: 1/5 + 1/20 = 1/6 + 1/12 = 1/8 + 1/8 = 1/4. What is the least value of n for which the number of distinct solutions exceeds one thousand?
Your task is to solve Amazon’s question; you might also like to make a list of the x, y pairs that sum to a given n. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.
Programming Praxis 