English
Coindep is defined as independence in the dual of the matroid; a set I is coindependent in M iff I is independent in M✶.
Русский
Коиндеп определяется как независимость в двойственном матроиде; множество I коиндепендентно в M тогда и только тогда, когда I независимо в M✶.
LaTeX
$$$ \operatorname{Coindep}(M,I) \iff M^{\ast}.Indep(I)$$$
Lean4
/-- A coindependent set of `M` is an independent set of the dual of `M✶`. we give it a separate
definition to enable dot notation. Which spelling is better depends on context. -/
abbrev Coindep (M : Matroid α) (I : Set α) : Prop :=
M✶.Indep I