English
The Pi-space of a family of R0 spaces is R0.
Русский
Произведение по индексному множеству из пространств R0 образует R0-пространство.
LaTeX
$$$R0Space(\\forall i, X_i)$$$
Lean4
/-- In an R₀ space, relatively compact sets form a bornology.
Its cobounded filter is `Filter.coclosedCompact`.
See also `Bornology.inCompact` the bornology of sets contained in a compact set. -/
def relativelyCompact : Bornology X where
cobounded := Filter.coclosedCompact X
le_cofinite := Filter.coclosedCompact_le_cofinite