Mertens
From specialfunctionswiki
Let $n \in \mathbb{Z}^+$. Define the Mertens function $$M(n)=\displaystyle\sum_{k=1}^n \mu(k),$$ where $\mu$ is the [Möbius function].
Let $n \in \mathbb{Z}^+$. Define the Mertens function $$M(n)=\displaystyle\sum_{k=1}^n \mu(k),$$ where $\mu$ is the [Möbius function].