English
Naturality of the associator with respect to biprod.map: biprod.map (biprod.map f g) h ≫ biprod.associator .hom = biprod.associator .hom ≫ biprod.map f (biprod.map g h).
Русский
Натурализм ассоциатора относительно biprod.map: biprod.map (biprod.map f g) h ≫ associator.hom = associator.hom ≫ biprod.map f (biprod.map g h).
LaTeX
$$$\mathrm{biprod.map} (\mathrm{biprod.map} f g)\, h \;\;≫\; \mathrm{biprod.associator} X Y Z \;\mathrm{hom} = \mathrm{biprod.associator} U V W \;\mathrm{hom} \;≫\; \mathrm{biprod.map} f (\mathrm{biprod.map} g h)$$$
Lean4
@[reassoc (attr := simp)]
theorem symmetry' (P Q : C) : biprod.lift biprod.snd biprod.fst ≫ biprod.lift biprod.snd biprod.fst = 𝟙 (P ⊞ Q) := by
cat_disch