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| -rw-r--r-- | library/topology/basis.tex | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/library/topology/basis.tex b/library/topology/basis.tex index dda187c..bca42f0 100644 --- a/library/topology/basis.tex +++ b/library/topology/basis.tex @@ -43,3 +43,8 @@ for all $U, V, x$ such that $U, V\in B$ and $x\in U,V$ there exists $W\in B$ such that $x\in W\subseteq U, V$. \end{definition} + +\begin{definition}\label{genOpens} + $\genOpens{B}{X} = \{ U\in\pow{X} \mid for all $x\in U$ there exists $V\in B$ + such that $x\in V\subseteq U$\}$. +\end{definition} |