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> [!definition] Definition. ([[semigroup]])
> A **semigroup** is a pair $(G, \cdot)$ consisting of a set $G$ and a [[binary operation]] $\cdot: G \times G \to G$ that is [[associative]].
> \
> Semigroups may be considered generalizations of [[group|groups]] that remove the requirements of identity and inverses.
> [!basicexample]
> $\mathbb{N}$ forms a [[semigroup]] under addition.
^basic-example
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####
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#### References
> [!backlink]
> ```dataview
> TABLE rows.file.link as "Further Reading"
> FROM [[]]
> FLATTEN file.tags as Tag
> WHERE Tag = "#definition" OR Tag = "#theorem" OR Tag = "#MOC" OR Tag = "#proposition" OR Tag = "#axiom"
> GROUP BY Tag
> ```
> [!frontlink]
> ```dataview
> TABLE rows.file.link as "Further Reading"
> FROM outgoing([[]])
> FLATTEN file.tags as Tag
> WHERE Tag = "#definition" OR Tag = "#theorem" OR Tag = "#MOC" OR Tag = "#proposition" OR Tag = "#axiom"
> GROUP BY Tag
> ```