A simple question about 1-norm

Question

Let $\Gamma$ be a discrete group, if $\mu \in l^{1}(\Gamma)$, then what is the 1-norm of $\mu$, I mean $||\mu||_{1}=?$. As we know, $l^{1}(\Gamma)=\{(\alpha_{x})_{x\in\Gamma}: \sum\limits_{x}|\alpha_{x}|<\infty\}$, then $||\mu||_{1}=\sum\limits_{x}|\alpha_{x}|$?

Answer 1

Yes, this is a standard notation.