English
For every natural n, I.ι.f n is mono (reiterating the mono property in Nat-indexed family).
Русский
Для каждого натурального n множество I.ι.f n моно; повторение моно свойства для семейства с индексами по Nat.
LaTeX
$$$\forall n\in\mathbb{N},\; Mono(I.ι.f\,n)$$$
Lean4
/-- A functor between preadditive categories preserves all equalizers if it preserves all kernels.
-/
theorem preservesEqualizers_of_preservesKernels [∀ {X Y} (f : X ⟶ Y), PreservesLimit (parallelPair f 0) F] :
PreservesLimitsOfShape WalkingParallelPair F where
preservesLimit
{K} :=
by
letI :=
preservesEqualizer_of_preservesKernels F (K.map WalkingParallelPairHom.left) (K.map WalkingParallelPairHom.right)
apply preservesLimit_of_iso_diagram F (diagramIsoParallelPair K).symm