English
Constructor for morphisms from the mapBifunctor₂₃ X j component is provided by a GradedObject-level descent map.
Русский
Конструктор для морфизмов из компонента mapBifunctor₂₃ X j задаётся через градацию descent-маршрута.
LaTeX
$$$mapBifunctor₂₃Desc$ defines the morphism from X_j to A$$
Lean4
theorem ι_eq (i₁ : ι₁) (i₂ : ι₂) (i₃ : ι₃) (i₂₃ : ι₂₃) (j : ι₄) (h₂₃ : ComplexShape.π c₂ c₃ c₂₃ ⟨i₂, i₃⟩ = i₂₃)
(h : ComplexShape.π c₁ c₂₃ c₄ (i₁, i₂₃) = j) :
ι F G₂₃ K₁ K₂ K₃ c₁₂ c₂₃ c₄ i₁ i₂ i₃ j (by rw [← h, ← h₂₃, ← ComplexShape.assoc c₁ c₂ c₃ c₁₂ c₂₃ c₄]; rfl) =
(F.obj (K₁.X i₁)).map (ιMapBifunctor K₂ K₃ G₂₃ c₂₃ i₂ i₃ i₂₃ h₂₃) ≫
ιMapBifunctor K₁ (mapBifunctor K₂ K₃ G₂₃ c₂₃) F c₄ i₁ i₂₃ j h :=
by
subst h₂₃
rfl