User:Jshflynn/Definition:Kleene plus

Definition
Let $\Sigma$ be an alphabet.

Let $V$ be a subalphabet of $\Sigma$.

Then the Kleene plus of $V$ is denoted $V^{+}$ and defined:



\displaystyle \bigcup_{i \in \mathbb{N}_{>0}} V^{i} $

Synonyms
Some authors call this:


 * Semigroup closure