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Theorems · Theorem · category theory

CategoryTheory.any_functor_const_on_obj

∀ {J : Type u₁} [inst : CategoryTheory.Category.{v₁, u₁} J] [CategoryTheory.IsPreconnected J] {α : Type u₂}
  (F : CategoryTheory.Functor J (CategoryTheory.Discrete α)) (j j' : J), F.obj j = F.obj j'

If J is connected, any functor to a discrete category is constant on objects. The converse is given in IsConnected.of_any_functor_const_on_obj.

Defined in
Mathlib.CategoryTheory.IsConnected
Cited by
1 results in Mathlib
Foundations
Depth 29 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes
CategoryTheory.CategoryCategoryTheory.IsPreconnected

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