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PROJECT EULER · #0110

Diophantine Reciprocals II

Statement only · SolvedOriginal problem ↗

In the following equation x, y, and n are positive integers.

1x+1y=1n

It can be verified that when n=1260 there are 113 distinct solutions and this is the least value of n for which the total number of distinct solutions exceeds one hundred.

What is the least value of n for which the number of distinct solutions exceeds four million?

NOTE: This problem is a much more difficult version of Problem 108 and as it is well beyond the limitations of a brute force approach it requires a clever implementation.

Write-up coming later

The complete problem is available here. An approach, code, and answer will be added later.