Project Euler Problem 541
The nth harmonic number Hn is defined as the sum of the multiplicative inverses of the first n positive integers, and ca
Solution
Answer: 4580726482872451
I derived and independently verified the computation using a $p$-adic lifting approach for harmonic numbers, together with a direct implementation that reproduces the given checks:
- $M(3)=68$
- $M(7)=719102$
The computation for $p=137$ yields:
Answer: 4580726482872451