Finset.map_subtype_subset

∀ {α : Type u_1} {t : Set α} (s : Finset ↑t), ↑(Finset.map (Function.Embedding.subtype fun x => x ∈ t) s) ⊆ t

If a Finset of a subtype is converted to the main type with Embedding.subtype, the result is a subset of the set giving the subtype.

Defined in: Mathlib.Data.Finset.Image
Cited by: 5 results in Mathlib
Foundations: Depth 56 from the axioms · uses propext, Classical.choice, Quot.sound

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