English
If M.E = E and N.E = E and M.restrictSubtype E = N.restrictSubtype E, then M = N.
Русский
Если M.Е = E и N.Е = E и M.restrictSubtype E = N.restrictSubtype E, то M = N.
LaTeX
$$Eq M.E E → Eq N.E E → Eq (M.restrictSubtype E) (N.restrictSubtype E) → Eq M N$$
Lean4
theorem eq_of_restrictSubtype_eq {N : Matroid α} (hM : M.E = E) (hN : N.E = E)
(h : M.restrictSubtype E = N.restrictSubtype E) : M = N :=
by
subst hM
refine ext_indep (by rw [hN]) (fun I hI ↦ ?_)
rwa [← restrictSubtype_indep_iff_of_subset hI, h, restrictSubtype_indep_iff_of_subset]