| context | $p\in \mathbb N$ |
| definiendum | $\mathfrak J^p\equiv\{\ ]a,b]\ |\ a,b\in\mathbb R^p\ \land\ a\le b\}$ |
This set is one which generates the $\sigma$-Algebra $\mathcal B^p$ of Borel subset of $\mathbb R^p$.
We also write
| definiendum | $\mathfrak J\equiv \mathfrak J^1$ |