Minimal Element/Examples

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Examples of Minimal Elements

Finite Subsets of Natural Numbers

Let $\FF$ denote the set of finite subsets of the natural numbers $\N$.

Consider the ordered set $\struct {\FF, \subseteq}$.

There is one minimal element of $\struct {\FF, \subseteq}$, and that is the empty set $\O$.


Finite Subsets of Natural Numbers less Empty Set

Let $\FF$ denote the set of finite subsets of the natural numbers $\N$.

Let $\GG$ denote the set $\FF \setminus \O$, that is, $\FF$ with the empty set excluded.

Consider the ordered set $\struct {\GG, \subseteq}$.


The minimal elements of $\struct {\GG, \subseteq}$ are the sets of the form $\set n$, for $n \in \N$.