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Mathlib.Algebra.Group.Action.Pointwise.Set.Finite

Finiteness lemmas for pointwise operations on sets #

@[simp]
theorem Set.finite_smul_set {G : Type u_1} {α : Type u_2} [Group G] [MulAction G α] {a : G} {s : Set α} :
@[simp]
theorem Set.finite_vadd_set {G : Type u_1} {α : Type u_2} [AddGroup G] [AddAction G α] {a : G} {s : Set α} :
@[simp]
theorem Set.infinite_smul_set {G : Type u_1} {α : Type u_2} [Group G] [MulAction G α] {a : G} {s : Set α} :
@[simp]
theorem Set.infinite_vadd_set {G : Type u_1} {α : Type u_2} [AddGroup G] [AddAction G α] {a : G} {s : Set α} :
theorem Set.Finite.of_smul_set {G : Type u_1} {α : Type u_2} [Group G] [MulAction G α] {a : G} {s : Set α} :
(a s).Finites.Finite

Alias of the forward direction of Set.finite_smul_set.

theorem Set.Finite.of_vadd_set {G : Type u_1} {α : Type u_2} [AddGroup G] [AddAction G α] {a : G} {s : Set α} :
(a +ᵥ s).Finites.Finite
theorem Set.Infinite.smul_set {G : Type u_1} {α : Type u_2} [Group G] [MulAction G α] {a : G} {s : Set α} :
s.Infinite(a s).Infinite

Alias of the reverse direction of Set.infinite_smul_set.

theorem Set.Infinite.vadd_set {G : Type u_1} {α : Type u_2} [AddGroup G] [AddAction G α] {a : G} {s : Set α} :
s.Infinite(a +ᵥ s).Infinite