Tag Archives: Euler’s totient function

The Möbius function, denoted \(\mu\), is defined as$$\mu(n) =\begin{cases}1 & \text{if } n = 1, \\(-1)^k & \text{if $n = p_1 \dots p_k$, where $p_1, \dots, p_k$ are distinct primes}, \\0 & \text{otherwise}.\end{cases}$$It is the signed characteristic function of squarefree … Continue reading →