English
The symmetric of sumCongr equals the sumCongr of symmetric components for permutations.
Русский
Симметрическая части sumCongr равна sumCongr симметричных компонентов перестановок.
LaTeX
$$sumCongr_symm {α β} (e : Equiv.Perm α) (f : Equiv.Perm β) : (sumCongr e f).symm = sumCongr e.symm f.symm$$
Lean4
theorem sumCongr_symm {α β} (e : Equiv.Perm α) (f : Equiv.Perm β) : (sumCongr e f).symm = sumCongr e.symm f.symm :=
Equiv.sumCongr_symm e f