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summable.has_sum_iff (h : summable f) : has_sum f a ↔ ∑'b, f b = a
iff.intro has_sum.tsum_eq (assume eq, eq ▸ h.has_sum)
lemma
summable.has_sum_iff
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum", "has_sum.tsum_eq", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_empty [is_empty β] : ∑'b, f b = 0
has_sum_empty.tsum_eq
lemma
tsum_empty
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "is_empty" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_eq_sum {f : β → α} {s : finset β} (hf : ∀b∉s, f b = 0) : ∑' b, f b = ∑ b in s, f b
(has_sum_sum_of_ne_finset_zero hf).tsum_eq
lemma
tsum_eq_sum
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset", "has_sum_sum_of_ne_finset_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sum_eq_tsum_indicator (f : β → α) (s : finset β) : ∑ x in s, f x = ∑' x, set.indicator ↑s f x
have ∀ x ∉ s, set.indicator ↑s f x = 0, from λ x hx, set.indicator_apply_eq_zero.2 (λ hx', (hx $ finset.mem_coe.1 hx').elim), (finset.sum_congr rfl (λ x hx, (set.indicator_apply_eq_self.2 $ λ hx', (hx' $ finset.mem_coe.2 hx).elim).symm)).trans (tsum_eq_sum this).symm
lemma
sum_eq_tsum_indicator
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset", "set.indicator", "tsum_eq_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_congr {α β : Type*} [add_comm_monoid α] [topological_space α] {f g : β → α} (hfg : ∀ b, f b = g b) : ∑' b, f b = ∑' b, g b
congr_arg tsum (funext hfg)
lemma
tsum_congr
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "add_comm_monoid", "topological_space", "tsum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_fintype [fintype β] (f : β → α) : ∑'b, f b = ∑ b, f b
(has_sum_fintype f).tsum_eq
lemma
tsum_fintype
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "fintype", "has_sum_fintype" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_bool (f : bool → α) : ∑' i : bool, f i = f false + f true
by { rw [tsum_fintype, finset.sum_eq_add]; simp }
lemma
tsum_bool
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "tsum_fintype" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_eq_single {f : β → α} (b : β) (hf : ∀b' ≠ b, f b' = 0) : ∑'b, f b = f b
(has_sum_single b hf).tsum_eq
lemma
tsum_eq_single
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum_single" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_tsum_eq_single (f : β → γ → α) (b : β) (c : γ) (hfb : ∀ b' ≠ b, f b' c = 0) (hfc : ∀ (b' : β) (c' : γ), c' ≠ c → f b' c' = 0) : ∑' b' c', f b' c' = f b c
calc ∑' b' c', f b' c' = ∑' b', f b' c : tsum_congr $ λ b', tsum_eq_single _ (hfc b') ... = f b c : tsum_eq_single _ hfb
lemma
tsum_tsum_eq_single
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "tsum_congr", "tsum_eq_single" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_ite_eq (b : β) [decidable_pred (= b)] (a : α) : ∑' b', (if b' = b then a else 0) = a
(has_sum_ite_eq b a).tsum_eq
lemma
tsum_ite_eq
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum_ite_eq" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_pi_single [decidable_eq β] (b : β) (a : α) : ∑' b', pi.single b a b' = a
(has_sum_pi_single b a).tsum_eq
lemma
tsum_pi_single
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum_pi_single" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_dite_right (P : Prop) [decidable P] (x : β → ¬ P → α) : ∑' (b : β), (if h : P then (0 : α) else x b h) = if h : P then (0 : α) else ∑' (b : β), x b h
by by_cases hP : P; simp [hP]
lemma
tsum_dite_right
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_dite_left (P : Prop) [decidable P] (x : β → P → α) : ∑' (b : β), (if h : P then x b h else 0) = if h : P then (∑' (b : β), x b h) else 0
by by_cases hP : P; simp [hP]
lemma
tsum_dite_left
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
function.surjective.tsum_eq_tsum_of_has_sum_iff_has_sum {α' : Type*} [add_comm_monoid α'] [topological_space α'] {e : α' → α} (hes : function.surjective e) (h0 : e 0 = 0) {f : β → α} {g : γ → α'} (h : ∀ {a}, has_sum f (e a) ↔ has_sum g a) : ∑' b, f b = e (∑' c, g c)
by_cases (assume : summable g, (h.mpr this.has_sum).tsum_eq) (assume hg : ¬ summable g, have hf : ¬ summable f, from mt (hes.summable_iff_of_has_sum_iff @h).1 hg, by simp [tsum, hf, hg, h0])
lemma
function.surjective.tsum_eq_tsum_of_has_sum_iff_has_sum
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "add_comm_monoid", "has_sum", "summable", "topological_space", "tsum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_eq_tsum_of_has_sum_iff_has_sum {f : β → α} {g : γ → α} (h : ∀{a}, has_sum f a ↔ has_sum g a) : ∑'b, f b = ∑'c, g c
surjective_id.tsum_eq_tsum_of_has_sum_iff_has_sum rfl @h
lemma
tsum_eq_tsum_of_has_sum_iff_has_sum
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
equiv.tsum_eq (j : γ ≃ β) (f : β → α) : ∑'c, f (j c) = ∑'b, f b
tsum_eq_tsum_of_has_sum_iff_has_sum $ λ a, j.has_sum_iff
lemma
equiv.tsum_eq
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "tsum_eq_tsum_of_has_sum_iff_has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
equiv.tsum_eq_tsum_of_support {f : β → α} {g : γ → α} (e : support f ≃ support g) (he : ∀ x, g (e x) = f x) : (∑' x, f x) = ∑' y, g y
tsum_eq_tsum_of_has_sum_iff_has_sum $ λ _, e.has_sum_iff_of_support he
lemma
equiv.tsum_eq_tsum_of_support
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "tsum_eq_tsum_of_has_sum_iff_has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_eq_tsum_of_ne_zero_bij {g : γ → α} (i : support g → β) (hi : ∀ ⦃x y⦄, i x = i y → (x : γ) = y) (hf : support f ⊆ set.range i) (hfg : ∀ x, f (i x) = g x) : ∑' x, f x = ∑' y, g y
tsum_eq_tsum_of_has_sum_iff_has_sum $ λ _, has_sum_iff_has_sum_of_ne_zero_bij i hi hf hfg
lemma
tsum_eq_tsum_of_ne_zero_bij
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum_iff_has_sum_of_ne_zero_bij", "set.range", "tsum_eq_tsum_of_has_sum_iff_has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
finset.tsum_subtype (s : finset β) (f : β → α) : ∑' x : {x // x ∈ s}, f x = ∑ x in s, f x
(s.has_sum f).tsum_eq
lemma
finset.tsum_subtype
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
finset.tsum_subtype' (s : finset β) (f : β → α) : ∑' x : (s : set β), f x = ∑ x in s, f x
s.tsum_subtype f
lemma
finset.tsum_subtype'
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_subtype (s : set β) (f : β → α) : ∑' x : s, f x = ∑' x, s.indicator f x
tsum_eq_tsum_of_has_sum_iff_has_sum $ λ _, has_sum_subtype_iff_indicator
lemma
tsum_subtype
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum_subtype_iff_indicator", "tsum_eq_tsum_of_has_sum_iff_has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_subtype_eq_of_support_subset {f : β → α} {s : set β} (hs : support f ⊆ s) : ∑' x : s, f x = ∑' x, f x
tsum_eq_tsum_of_has_sum_iff_has_sum $ λ x, has_sum_subtype_iff_of_support_subset hs
lemma
tsum_subtype_eq_of_support_subset
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum_subtype_iff_of_support_subset", "tsum_eq_tsum_of_has_sum_iff_has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_univ (f : β → α) : ∑' x : (set.univ : set β), f x = ∑' x, f x
tsum_subtype_eq_of_support_subset $ set.subset_univ _
lemma
tsum_univ
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "set.subset_univ", "tsum_subtype_eq_of_support_subset" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_singleton (b : β) (f : β → α) : ∑' x : ({b} : set β), f x = f b
begin rw [tsum_subtype, tsum_eq_single b], { simp }, { intros b' hb', rw set.indicator_of_not_mem, rwa set.mem_singleton_iff }, { apply_instance } end
lemma
tsum_singleton
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "set.mem_singleton_iff", "tsum_eq_single", "tsum_subtype" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_image {g : γ → β} (f : β → α) {s : set γ} (hg : set.inj_on g s) : ∑' x : g '' s, f x = ∑' x : s, f (g x)
((equiv.set.image_of_inj_on _ _ hg).tsum_eq (λ x, f x)).symm
lemma
tsum_image
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "equiv.set.image_of_inj_on", "set.inj_on" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_range {g : γ → β} (f : β → α) (hg : injective g) : ∑' x : set.range g, f x = ∑' x, f (g x)
by rw [← set.image_univ, tsum_image f (hg.inj_on _), tsum_univ (f ∘ g)]
lemma
tsum_range
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "set.image_univ", "set.range", "tsum_image", "tsum_univ" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_add (hf : summable f) (hg : summable g) : ∑'b, (f b + g b) = (∑'b, f b) + (∑'b, g b)
(hf.has_sum.add hg.has_sum).tsum_eq
lemma
tsum_add
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_sum {f : γ → β → α} {s : finset γ} (hf : ∀i∈s, summable (f i)) : ∑'b, ∑ i in s, f i b = ∑ i in s, ∑'b, f i b
(has_sum_sum $ assume i hi, (hf i hi).has_sum).tsum_eq
lemma
tsum_sum
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset", "has_sum", "has_sum_sum", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_eq_add_tsum_ite' {f : β → α} (b : β) (hf : summable (f.update b 0)) : ∑' x, f x = f b + ∑' x, ite (x = b) 0 (f x)
calc ∑' x, f x = ∑' x, ((ite (x = b) (f x) 0) + (f.update b 0 x)) : tsum_congr (λ n, by split_ifs; simp [function.update_apply, h]) ... = ∑' x, ite (x = b) (f x) 0 + ∑' x, f.update b 0 x : tsum_add ⟨ite (b = b) (f b) 0, has_sum_single b (λ b hb, if_neg hb)⟩ (hf) ... = (ite (b = b) (f b) 0) + ∑' x, f.update ...
lemma
tsum_eq_add_tsum_ite'
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "dite_eq_ite", "eq_rec_constant", "has_sum_single", "summable", "tsum_add", "tsum_congr", "tsum_eq_single" ]
Version of `tsum_eq_add_tsum_ite` for `add_comm_monoid` rather than `add_comm_group`. Requires a different convergence assumption involving `function.update`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_sigma' {γ : β → Type*} {f : (Σb:β, γ b) → δ} (h₁ : ∀b, summable (λc, f ⟨b, c⟩)) (h₂ : summable f) : ∑'p, f p = ∑'b c, f ⟨b, c⟩
(h₂.has_sum.sigma (assume b, (h₁ b).has_sum)).tsum_eq.symm
lemma
tsum_sigma'
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_prod' {f : β × γ → δ} (h : summable f) (h₁ : ∀b, summable (λc, f (b, c))) : ∑'p, f p = ∑'b c, f (b, c)
(h.has_sum.prod_fiberwise (assume b, (h₁ b).has_sum)).tsum_eq.symm
lemma
tsum_prod'
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_comm' {f : β → γ → δ} (h : summable (function.uncurry f)) (h₁ : ∀b, summable (f b)) (h₂ : ∀ c, summable (λ b, f b c)) : ∑' c b, f b c = ∑' b c, f b c
begin erw [← tsum_prod' h h₁, ← tsum_prod' h.prod_symm h₂, ← (equiv.prod_comm γ β).tsum_eq (uncurry f)], refl end
lemma
tsum_comm'
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "equiv.prod_comm", "summable", "tsum_prod'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_supr_decode₂ [complete_lattice β] (m : β → α) (m0 : m ⊥ = 0) (s : γ → β) : ∑' i : ℕ, m (⨆ b ∈ decode₂ γ i, s b) = ∑' b : γ, m (s b)
begin have H : ∀ n, m (⨆ b ∈ decode₂ γ n, s b) ≠ 0 → (decode₂ γ n).is_some, { intros n h, cases decode₂ γ n with b, { refine (h $ by simp [m0]).elim }, { exact rfl } }, symmetry, refine tsum_eq_tsum_of_ne_zero_bij (λ a, option.get (H a.1 a.2)) _ _ _, { rintros ⟨m, hm⟩ ⟨n, hn⟩ e, have := mem_deco...
theorem
tsum_supr_decode₂
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "complete_lattice", "option.get_mem", "option.get_of_mem", "option.some_get", "set.ext_iff", "subtype.coe_mk", "tsum_eq_tsum_of_ne_zero_bij" ]
You can compute a sum over an encodably type by summing over the natural numbers and taking a supremum. This is useful for outer measures.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_Union_decode₂ (m : set β → α) (m0 : m ∅ = 0) (s : γ → set β) : ∑' i, m (⋃ b ∈ decode₂ γ i, s b) = ∑' b, m (s b)
tsum_supr_decode₂ m m0 s
theorem
tsum_Union_decode₂
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "tsum_supr_decode₂" ]
`tsum_supr_decode₂` specialized to the complete lattice of sets.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
rel_supr_tsum [complete_lattice β] (m : β → α) (m0 : m ⊥ = 0) (R : α → α → Prop) (m_supr : ∀(s : ℕ → β), R (m (⨆ i, s i)) ∑' i, m (s i)) (s : γ → β) : R (m (⨆ b : γ, s b)) ∑' b : γ, m (s b)
by { casesI nonempty_encodable γ, rw [←supr_decode₂, ←tsum_supr_decode₂ _ m0 s], exact m_supr _ }
theorem
rel_supr_tsum
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "complete_lattice", "nonempty_encodable" ]
If a function is countably sub-additive then it is sub-additive on countable types
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
rel_supr_sum [complete_lattice β] (m : β → α) (m0 : m ⊥ = 0) (R : α → α → Prop) (m_supr : ∀(s : ℕ → β), R (m (⨆ i, s i)) (∑' i, m (s i))) (s : δ → β) (t : finset δ) : R (m (⨆ d ∈ t, s d)) (∑ d in t, m (s d))
by { rw [supr_subtype', ←finset.tsum_subtype], exact rel_supr_tsum m m0 R m_supr _ }
theorem
rel_supr_sum
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "complete_lattice", "finset", "rel_supr_tsum", "supr_subtype'" ]
If a function is countably sub-additive then it is sub-additive on finite sets
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
rel_sup_add [complete_lattice β] (m : β → α) (m0 : m ⊥ = 0) (R : α → α → Prop) (m_supr : ∀(s : ℕ → β), R (m (⨆ i, s i)) (∑' i, m (s i))) (s₁ s₂ : β) : R (m (s₁ ⊔ s₂)) (m s₁ + m s₂)
begin convert rel_supr_tsum m m0 R m_supr (λ b, cond b s₁ s₂), { simp only [supr_bool_eq, cond] }, { rw [tsum_fintype, fintype.sum_bool, cond, cond] } end
theorem
rel_sup_add
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "complete_lattice", "rel_supr_tsum", "supr_bool_eq", "tsum_fintype" ]
If a function is countably sub-additive then it is binary sub-additive
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_add_tsum_compl {s : set β} (hs : summable (f ∘ coe : s → α)) (hsc : summable (f ∘ coe : sᶜ → α)) : (∑' x : s, f x) + (∑' x : sᶜ, f x) = ∑' x, f x
(hs.has_sum.add_compl hsc.has_sum).tsum_eq.symm
lemma
tsum_add_tsum_compl
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_union_disjoint {s t : set β} (hd : disjoint s t) (hs : summable (f ∘ coe : s → α)) (ht : summable (f ∘ coe : t → α)) : (∑' x : s ∪ t, f x) = (∑' x : s, f x) + (∑' x : t, f x)
(hs.has_sum.add_disjoint hd ht.has_sum).tsum_eq
lemma
tsum_union_disjoint
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "disjoint", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_finset_bUnion_disjoint {ι} {s : finset ι} {t : ι → set β} (hd : (s : set ι).pairwise (disjoint on t)) (hf : ∀ i ∈ s, summable (f ∘ coe : t i → α)) : (∑' x : (⋃ i ∈ s, t i), f x) = ∑ i in s, ∑' x : t i, f x
(has_sum_sum_disjoint _ hd (λ i hi, (hf i hi).has_sum)).tsum_eq
lemma
tsum_finset_bUnion_disjoint
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "disjoint", "finset", "has_sum", "has_sum_sum_disjoint", "pairwise", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_even_add_odd {f : ℕ → α} (he : summable (λ k, f (2 * k))) (ho : summable (λ k, f (2 * k + 1))) : (∑' k, f (2 * k)) + (∑' k, f (2 * k + 1)) = ∑' k, f k
(he.has_sum.even_add_odd ho.has_sum).tsum_eq.symm
lemma
tsum_even_add_odd
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.neg (h : has_sum f a) : has_sum (λb, - f b) (- a)
by simpa only using h.map (-add_monoid_hom.id α) continuous_neg
lemma
has_sum.neg
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.neg (hf : summable f) : summable (λb, - f b)
hf.has_sum.neg.summable
lemma
summable.neg
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.of_neg (hf : summable (λb, - f b)) : summable f
by simpa only [neg_neg] using hf.neg
lemma
summable.of_neg
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable_neg_iff : summable (λ b, - f b) ↔ summable f
⟨summable.of_neg, summable.neg⟩
lemma
summable_neg_iff
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.sub (hf : has_sum f a₁) (hg : has_sum g a₂) : has_sum (λb, f b - g b) (a₁ - a₂)
by { simp only [sub_eq_add_neg], exact hf.add hg.neg }
lemma
has_sum.sub
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.sub (hf : summable f) (hg : summable g) : summable (λb, f b - g b)
(hf.has_sum.sub hg.has_sum).summable
lemma
summable.sub
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.trans_sub (hg : summable g) (hfg : summable (λb, f b - g b)) : summable f
by simpa only [sub_add_cancel] using hfg.add hg
lemma
summable.trans_sub
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable_iff_of_summable_sub (hfg : summable (λb, f b - g b)) : summable f ↔ summable g
⟨λ hf, hf.trans_sub $ by simpa only [neg_sub] using hfg.neg, λ hg, hg.trans_sub hfg⟩
lemma
summable_iff_of_summable_sub
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.update (hf : has_sum f a₁) (b : β) [decidable_eq β] (a : α) : has_sum (update f b a) (a - f b + a₁)
begin convert ((has_sum_ite_eq b _).add hf), ext b', by_cases h : b' = b, { rw [h, update_same], simp only [eq_self_iff_true, if_true, sub_add_cancel] }, simp only [h, update_noteq, if_false, ne.def, zero_add, not_false_iff], end
lemma
has_sum.update
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum", "has_sum_ite_eq", "update", "update_noteq", "update_same" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.update (hf : summable f) (b : β) [decidable_eq β] (a : α) : summable (update f b a)
(hf.has_sum.update b a).summable
lemma
summable.update
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable", "update" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.has_sum_compl_iff {s : set β} (hf : has_sum (f ∘ coe : s → α) a₁) : has_sum (f ∘ coe : sᶜ → α) a₂ ↔ has_sum f (a₁ + a₂)
begin refine ⟨λ h, hf.add_compl h, λ h, _⟩, rw [has_sum_subtype_iff_indicator] at hf ⊢, rw [set.indicator_compl], simpa only [add_sub_cancel'] using h.sub hf end
lemma
has_sum.has_sum_compl_iff
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum", "has_sum_subtype_iff_indicator", "set.indicator_compl" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.has_sum_iff_compl {s : set β} (hf : has_sum (f ∘ coe : s → α) a₁) : has_sum f a₂ ↔ has_sum (f ∘ coe : sᶜ → α) (a₂ - a₁)
iff.symm $ hf.has_sum_compl_iff.trans $ by rw [add_sub_cancel'_right]
lemma
has_sum.has_sum_iff_compl
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.summable_compl_iff {s : set β} (hf : summable (f ∘ coe : s → α)) : summable (f ∘ coe : sᶜ → α) ↔ summable f
⟨λ ⟨a, ha⟩, (hf.has_sum.has_sum_compl_iff.1 ha).summable, λ ⟨a, ha⟩, (hf.has_sum.has_sum_iff_compl.1 ha).summable⟩
lemma
summable.summable_compl_iff
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
finset.has_sum_compl_iff (s : finset β) : has_sum (λ x : {x // x ∉ s}, f x) a ↔ has_sum f (a + ∑ i in s, f i)
(s.has_sum f).has_sum_compl_iff.trans $ by rw [add_comm]
lemma
finset.has_sum_compl_iff
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset", "has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
finset.has_sum_iff_compl (s : finset β) : has_sum f a ↔ has_sum (λ x : {x // x ∉ s}, f x) (a - ∑ i in s, f i)
(s.has_sum f).has_sum_iff_compl
lemma
finset.has_sum_iff_compl
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset", "has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
finset.summable_compl_iff (s : finset β) : summable (λ x : {x // x ∉ s}, f x) ↔ summable f
(s.summable f).summable_compl_iff
lemma
finset.summable_compl_iff
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
set.finite.summable_compl_iff {s : set β} (hs : s.finite) : summable (f ∘ coe : sᶜ → α) ↔ summable f
(hs.summable f).summable_compl_iff
lemma
set.finite.summable_compl_iff
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum_ite_sub_has_sum [decidable_eq β] (hf : has_sum f a) (b : β) : has_sum (λ n, ite (n = b) 0 (f n)) (a - f b)
begin convert hf.update b 0 using 1, { ext n, rw function.update_apply, }, { rw [sub_add_eq_add_sub, zero_add], }, end
lemma
has_sum_ite_sub_has_sum
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_neg : ∑'b, - f b = - ∑'b, f b
begin by_cases hf : summable f, { exact hf.has_sum.neg.tsum_eq, }, { simp [tsum_eq_zero_of_not_summable hf, tsum_eq_zero_of_not_summable (mt summable.of_neg hf)] }, end
lemma
tsum_neg
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable", "summable.of_neg", "tsum_eq_zero_of_not_summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_sub (hf : summable f) (hg : summable g) : ∑'b, (f b - g b) = ∑'b, f b - ∑'b, g b
(hf.has_sum.sub hg.has_sum).tsum_eq
lemma
tsum_sub
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sum_add_tsum_compl {s : finset β} (hf : summable f) : (∑ x in s, f x) + (∑' x : (↑s : set β)ᶜ, f x) = ∑' x, f x
((s.has_sum f).add_compl (s.summable_compl_iff.2 hf).has_sum).tsum_eq.symm
lemma
sum_add_tsum_compl
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset", "has_sum", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_eq_add_tsum_ite [decidable_eq β] (hf : summable f) (b : β) : ∑' n, f n = f b + ∑' n, ite (n = b) 0 (f n)
begin rw (has_sum_ite_sub_has_sum hf.has_sum b).tsum_eq, exact (add_sub_cancel'_right _ _).symm, end
lemma
tsum_eq_add_tsum_ite
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum_ite_sub_has_sum", "summable" ]
Let `f : β → α` be a sequence with summable series and let `b ∈ β` be an index. Lemma `tsum_eq_add_tsum_ite` writes `Σ f n` as the sum of `f b` plus the series of the remaining terms.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum_nat_add_iff {f : ℕ → α} (k : ℕ) {a : α} : has_sum (λ n, f (n + k)) a ↔ has_sum f (a + ∑ i in range k, f i)
begin refine iff.trans _ ((range k).has_sum_compl_iff), rw [← (not_mem_range_equiv k).symm.has_sum_iff], refl end
lemma
has_sum_nat_add_iff
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum", "not_mem_range_equiv" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable_nat_add_iff {f : ℕ → α} (k : ℕ) : summable (λ n, f (n + k)) ↔ summable f
iff.symm $ (equiv.add_right (∑ i in range k, f i)).surjective.summable_iff_of_has_sum_iff $ λ a, (has_sum_nat_add_iff k).symm
lemma
summable_nat_add_iff
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum_nat_add_iff", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum_nat_add_iff' {f : ℕ → α} (k : ℕ) {a : α} : has_sum (λ n, f (n + k)) (a - ∑ i in range k, f i) ↔ has_sum f a
by simp [has_sum_nat_add_iff]
lemma
has_sum_nat_add_iff'
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum", "has_sum_nat_add_iff" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sum_add_tsum_nat_add [t2_space α] {f : ℕ → α} (k : ℕ) (h : summable f) : (∑ i in range k, f i) + (∑' i, f (i + k)) = ∑' i, f i
by simpa only [add_comm] using ((has_sum_nat_add_iff k).1 ((summable_nat_add_iff k).2 h).has_sum).unique h.has_sum
lemma
sum_add_tsum_nat_add
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum", "has_sum_nat_add_iff", "summable", "summable_nat_add_iff", "t2_space", "unique" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_eq_zero_add [t2_space α] {f : ℕ → α} (hf : summable f) : ∑'b, f b = f 0 + ∑'b, f (b + 1)
by simpa only [sum_range_one] using (sum_add_tsum_nat_add 1 hf).symm
lemma
tsum_eq_zero_add
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "sum_add_tsum_nat_add", "summable", "t2_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tendsto_sum_nat_add [t2_space α] (f : ℕ → α) : tendsto (λ i, ∑' k, f (k + i)) at_top (𝓝 0)
begin by_cases hf : summable f, { have h₀ : (λ i, (∑' i, f i) - ∑ j in range i, f j) = λ i, ∑' (k : ℕ), f (k + i), { ext1 i, rw [sub_eq_iff_eq_add, add_comm, sum_add_tsum_nat_add i hf] }, have h₁ : tendsto (λ i : ℕ, ∑' i, f i) at_top (𝓝 (∑' i, f i)) := tendsto_const_nhds, simpa only [h₀, sub_self...
lemma
tendsto_sum_nat_add
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "sum_add_tsum_nat_add", "summable", "summable_nat_add_iff", "t2_space", "tendsto_const_nhds", "tsum_eq_zero_of_not_summable" ]
For `f : ℕ → α`, then `∑' k, f (k + i)` tends to zero. This does not require a summability assumption on `f`, as otherwise all sums are zero.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.int_rec {b : α} {f g : ℕ → α} (hf : has_sum f a) (hg : has_sum g b) : @has_sum α _ _ _ (@int.rec (λ _, α) f g : ℤ → α) (a + b)
begin -- note this proof works for any two-case inductive have h₁ : injective (coe : ℕ → ℤ) := @int.of_nat.inj, have h₂ : injective int.neg_succ_of_nat := @int.neg_succ_of_nat.inj, have : is_compl (set.range (coe : ℕ → ℤ)) (set.range int.neg_succ_of_nat), { split, { rw disjoint_iff_inf_le, rintros _...
lemma
has_sum.int_rec
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "codisjoint_iff_le_sup", "disjoint_iff_inf_le", "has_sum", "has_sum.add_is_compl", "is_compl", "set.range" ]
If `f₀, f₁, f₂, ...` and `g₀, g₁, g₂, ...` are both convergent then so is the `ℤ`-indexed sequence: `..., g₂, g₁, g₀, f₀, f₁, f₂, ...`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.nonneg_add_neg {b : α} {f : ℤ → α} (hnonneg : has_sum (λ n : ℕ, f n) a) (hneg : has_sum (λ (n : ℕ), f (-n.succ)) b) : has_sum f (a + b)
begin simp_rw ← int.neg_succ_of_nat_coe at hneg, convert hnonneg.int_rec hneg using 1, ext (i | j); refl, end
lemma
has_sum.nonneg_add_neg
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.pos_add_zero_add_neg {b : α} {f : ℤ → α} (hpos : has_sum (λ n:ℕ, f(n + 1)) a) (hneg : has_sum (λ (n : ℕ), f (-n.succ)) b) : has_sum f (a + f 0 + b)
begin have : ∀ g : ℕ → α, has_sum (λ k, g (k + 1)) a → has_sum g (a + g 0), { intros g hg, simpa using (has_sum_nat_add_iff _).mp hg }, exact (this (λ n, f n) hpos).nonneg_add_neg hneg, end
lemma
has_sum.pos_add_zero_add_neg
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum", "has_sum_nat_add_iff" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable_int_of_summable_nat {f : ℤ → α} (hp : summable (λ n:ℕ, f n)) (hn : summable (λ n:ℕ, f (-n))) : summable f
(has_sum.nonneg_add_neg hp.has_sum $ summable.has_sum $ (summable_nat_add_iff 1).mpr hn).summable
lemma
summable_int_of_summable_nat
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum.nonneg_add_neg", "summable", "summable.has_sum", "summable_nat_add_iff" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.sum_nat_of_sum_int {α : Type*} [add_comm_monoid α] [topological_space α] [has_continuous_add α] {a : α} {f : ℤ → α} (hf : has_sum f a) : has_sum (λ n:ℕ, f n + f (-n)) (a + f 0)
begin apply (hf.add (has_sum_ite_eq (0 : ℤ) (f 0))).has_sum_of_sum_eq (λ u, _), refine ⟨u.image int.nat_abs, λ v' hv', _⟩, let u1 := v'.image (λ (x : ℕ), (x : ℤ)), let u2 := v'.image (λ (x : ℕ), - (x : ℤ)), have A : u ⊆ u1 ∪ u2, { assume x hx, simp only [mem_union, mem_image, exists_prop], rcases le...
lemma
has_sum.sum_nat_of_sum_int
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "abs_eq_self", "abs_of_nonpos", "add_comm_monoid", "exists_prop", "has_continuous_add", "has_sum", "has_sum_ite_eq", "imp_self", "int.coe_nat_abs", "nat.cast_inj", "nat.cast_nonneg", "topological_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable_iff_cauchy_seq_finset [complete_space α] {f : β → α} : summable f ↔ cauchy_seq (λ (s : finset β), ∑ b in s, f b)
cauchy_map_iff_exists_tendsto.symm
lemma
summable_iff_cauchy_seq_finset
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "cauchy_seq", "complete_space", "finset", "summable" ]
The **Cauchy criterion** for infinite sums, also known as the **Cauchy convergence test**
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
cauchy_seq_finset_iff_vanishing : cauchy_seq (λ (s : finset β), ∑ b in s, f b) ↔ ∀ e ∈ 𝓝 (0:α), (∃s:finset β, ∀t, disjoint t s → ∑ b in t, f b ∈ e)
begin simp only [cauchy_seq, cauchy_map_iff, and_iff_right at_top_ne_bot, prod_at_top_at_top_eq, uniformity_eq_comap_nhds_zero α, tendsto_comap_iff, (∘)], rw [tendsto_at_top'], split, { assume h e he, rcases h e he with ⟨⟨s₁, s₂⟩, h⟩, use [s₁ ∪ s₂], assume t ht, specialize h (s₁ ∪ s₂, (s₁ ∪ ...
lemma
cauchy_seq_finset_iff_vanishing
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "cauchy_map_iff", "cauchy_seq", "disjoint", "finset", "finset.sdiff_disjoint", "le_sup_of_le_left" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tendsto_tsum_compl_at_top_zero (f : β → α) : tendsto (λ (s : finset β), ∑' b : {x // x ∉ s}, f b) at_top (𝓝 0)
begin by_cases H : summable f, { assume e he, rcases exists_mem_nhds_is_closed_subset he with ⟨o, ho, o_closed, oe⟩, simp only [le_eq_subset, set.mem_preimage, mem_at_top_sets, filter.mem_map, ge_iff_le], obtain ⟨s, hs⟩ : ∃ (s : finset β), ∀ (t : finset β), disjoint t s → ∑ (b : β) in t, f b ∈ o := ...
lemma
tendsto_tsum_compl_at_top_zero
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "disjoint", "exists_mem_nhds_is_closed_subset", "filter.mem_map", "finset", "finset.image", "finset.summable_compl_iff", "ge_iff_le", "is_closed.mem_of_tendsto", "set.mem_preimage", "subtype.ext", "summable", "tendsto_const_nhds", "tsum_eq_zero_of_not_summable" ]
The sum over the complement of a finset tends to `0` when the finset grows to cover the whole space. This does not need a summability assumption, as otherwise all sums are zero.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable_iff_vanishing : summable f ↔ ∀ e ∈ 𝓝 (0:α), (∃s:finset β, ∀t, disjoint t s → ∑ b in t, f b ∈ e)
by rw [summable_iff_cauchy_seq_finset, cauchy_seq_finset_iff_vanishing]
lemma
summable_iff_vanishing
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "cauchy_seq_finset_iff_vanishing", "disjoint", "finset", "summable", "summable_iff_cauchy_seq_finset" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.summable_of_eq_zero_or_self (hf : summable f) (h : ∀b, g b = 0 ∨ g b = f b) : summable g
summable_iff_vanishing.2 $ assume e he, let ⟨s, hs⟩ := summable_iff_vanishing.1 hf e he in ⟨s, assume t ht, have eq : ∑ b in t.filter (λb, g b = f b), f b = ∑ b in t, g b := calc ∑ b in t.filter (λb, g b = f b), f b = ∑ b in t.filter (λb, g b = f b), g b : finset.sum_congr rfl (assume b hb, (f...
lemma
summable.summable_of_eq_zero_or_self
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset.disjoint_of_subset_left", "finset.filter_subset", "finset.mem_filter", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.indicator (hf : summable f) (s : set β) : summable (s.indicator f)
hf.summable_of_eq_zero_or_self $ set.indicator_eq_zero_or_self _ _
lemma
summable.indicator
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.comp_injective {i : γ → β} (hf : summable f) (hi : injective i) : summable (f ∘ i)
begin simpa only [set.indicator_range_comp] using (hi.summable_iff _).2 (hf.indicator (set.range i)), exact λ x hx, set.indicator_of_not_mem hx _ end
lemma
summable.comp_injective
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "set.range", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.subtype (hf : summable f) (s : set β) : summable (f ∘ coe : s → α)
hf.comp_injective subtype.coe_injective
lemma
summable.subtype
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "subtype.coe_injective", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable_subtype_and_compl {s : set β} : summable (λ x : s, f x) ∧ summable (λ x : sᶜ, f x) ↔ summable f
⟨and_imp.2 summable.add_compl, λ h, ⟨h.subtype s, h.subtype sᶜ⟩⟩
lemma
summable_subtype_and_compl
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable", "summable.add_compl" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.sigma_factor {γ : β → Type*} {f : (Σb:β, γ b) → α} (ha : summable f) (b : β) : summable (λc, f ⟨b, c⟩)
ha.comp_injective sigma_mk_injective
lemma
summable.sigma_factor
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "sigma_mk_injective", "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.sigma {γ : β → Type*} {f : (Σb:β, γ b) → α} (ha : summable f) : summable (λb, ∑'c, f ⟨b, c⟩)
ha.sigma' (λ b, ha.sigma_factor b)
lemma
summable.sigma
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.prod_factor {f : β × γ → α} (h : summable f) (b : β) : summable (λ c, f (b, c))
h.comp_injective $ λ c₁ c₂ h, (prod.ext_iff.1 h).2
lemma
summable.prod_factor
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_sigma [t0_space α] {γ : β → Type*} {f : (Σb:β, γ b) → α} (ha : summable f) : ∑'p, f p = ∑'b c, f ⟨b, c⟩
tsum_sigma' (λ b, ha.sigma_factor b) ha
lemma
tsum_sigma
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable", "t0_space", "tsum_sigma'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_prod [t0_space α] {f : β × γ → α} (h : summable f) : ∑'p, f p = ∑'b c, f ⟨b, c⟩
tsum_prod' h h.prod_factor
lemma
tsum_prod
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable", "t0_space", "tsum_prod'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_comm [t0_space α] {f : β → γ → α} (h : summable (function.uncurry f)) : ∑' c b, f b c = ∑' b c, f b c
tsum_comm' h h.prod_factor h.prod_symm.prod_factor
lemma
tsum_comm
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable", "t0_space", "tsum_comm'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_subtype_add_tsum_subtype_compl [t2_space α] {f : β → α} (hf : summable f) (s : set β) : ∑' x : s, f x + ∑' x : sᶜ, f x = ∑' x, f x
((hf.subtype s).has_sum.add_compl (hf.subtype {x | x ∉ s}).has_sum).unique hf.has_sum
lemma
tsum_subtype_add_tsum_subtype_compl
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "has_sum", "has_sum.add_compl", "summable", "t2_space", "unique" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sum_add_tsum_subtype_compl [t2_space α] {f : β → α} (hf : summable f) (s : finset β) : ∑ x in s, f x + ∑' x : {x // x ∉ s}, f x = ∑' x, f x
begin rw ← tsum_subtype_add_tsum_subtype_compl hf s, simp only [finset.tsum_subtype', add_right_inj], refl, end
lemma
sum_add_tsum_subtype_compl
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "finset", "finset.tsum_subtype'", "summable", "t2_space", "tsum_subtype_add_tsum_subtype_compl" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.vanishing (hf : summable f) ⦃e : set G⦄ (he : e ∈ 𝓝 (0 : G)) : ∃ s : finset α, ∀ t, disjoint t s → ∑ k in t, f k ∈ e
begin letI : uniform_space G := topological_add_group.to_uniform_space G, letI : uniform_add_group G := topological_add_comm_group_is_uniform, rcases hf with ⟨y, hy⟩, exact cauchy_seq_finset_iff_vanishing.1 hy.cauchy_seq e he end
lemma
summable.vanishing
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "disjoint", "finset", "summable", "uniform_add_group", "uniform_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.tendsto_cofinite_zero (hf : summable f) : tendsto f cofinite (𝓝 0)
begin intros e he, rw [filter.mem_map], rcases hf.vanishing he with ⟨s, hs⟩, refine s.eventually_cofinite_nmem.mono (λ x hx, _), by simpa using hs {x} (disjoint_singleton_left.2 hx) end
lemma
summable.tendsto_cofinite_zero
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "filter.mem_map", "summable" ]
Series divergence test: if `f` is a convergent series, then `f x` tends to zero along `cofinite`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.tendsto_at_top_zero {f : ℕ → G} (hf : summable f) : tendsto f at_top (𝓝 0)
by { rw ←nat.cofinite_eq_at_top, exact hf.tendsto_cofinite_zero }
lemma
summable.tendsto_at_top_zero
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.const_smul {a : α} (b : γ) (hf : has_sum f a) : has_sum (λ i, b • f i) (b • a)
hf.map (distrib_mul_action.to_add_monoid_hom α _) $ continuous_const_smul _
lemma
has_sum.const_smul
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "distrib_mul_action.to_add_monoid_hom", "has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
summable.const_smul (b : γ) (hf : summable f) : summable (λ i, b • f i)
(hf.has_sum.const_smul _).summable
lemma
summable.const_smul
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_const_smul [t2_space α] (b : γ) (hf : summable f) : ∑' i, b • f i = b • ∑' i, f i
(hf.has_sum.const_smul _).tsum_eq
lemma
tsum_const_smul
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "summable", "t2_space" ]
Infinite sums commute with scalar multiplication. Version for scalars living in a `monoid`, but requiring a summability hypothesis.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_const_smul' {γ : Type*} [group γ] [distrib_mul_action γ α] [has_continuous_const_smul γ α] [t2_space α] (g : γ) : ∑' (i : β), g • f i = g • ∑' (i : β), f i
begin by_cases hf : summable f, { exact tsum_const_smul _ hf, }, rw tsum_eq_zero_of_not_summable hf, simp only [smul_zero], let mul_g : α ≃+ α := distrib_mul_action.to_add_equiv α g, apply tsum_eq_zero_of_not_summable, change ¬ summable (mul_g ∘ f), rwa summable.map_iff_of_equiv mul_g; apply continuous_...
lemma
tsum_const_smul'
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "distrib_mul_action", "distrib_mul_action.to_add_equiv", "group", "has_continuous_const_smul", "smul_zero", "summable", "summable.map_iff_of_equiv", "t2_space", "tsum_const_smul", "tsum_eq_zero_of_not_summable" ]
Infinite sums commute with scalar multiplication. Version for scalars living in a `group`, but not requiring any summability hypothesis.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tsum_const_smul'' {γ : Type*} [division_ring γ] [module γ α] [has_continuous_const_smul γ α] [t2_space α] (g : γ) : ∑' (i : β), g • f i = g • ∑' (i : β), f i
begin by_cases hf : summable f, { exact tsum_const_smul _ hf, }, rw tsum_eq_zero_of_not_summable hf, simp only [smul_zero], by_cases hg : g = 0, { simp [hg], }, let mul_g : α ≃+ α := distrib_mul_action.to_add_equiv₀ α g hg, apply tsum_eq_zero_of_not_summable, change ¬ summable (mul_g ∘ f), rwa summa...
lemma
tsum_const_smul''
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "distrib_mul_action.to_add_equiv₀", "division_ring", "has_continuous_const_smul", "module", "smul_zero", "summable", "summable.map_iff_of_equiv", "t2_space", "tsum_const_smul", "tsum_eq_zero_of_not_summable" ]
Infinite sums commute with scalar multiplication. Version for scalars living in a `division_ring`; no summability hypothesis. This could be made to work for a `[group_with_zero γ]` if there was such a thing as `distrib_mul_action_with_zero`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_sum.prod_mk {f : β → α} {g : β → γ} {a : α} {b : γ} (hf : has_sum f a) (hg : has_sum g b) : has_sum (λ x, (⟨f x, g x⟩ : α × γ)) ⟨a, b⟩
by simp [has_sum, ← prod_mk_sum, filter.tendsto.prod_mk_nhds hf hg]
lemma
has_sum.prod_mk
topology.algebra.infinite_sum
src/topology/algebra/infinite_sum/basic.lean
[ "data.nat.parity", "logic.encodable.lattice", "topology.algebra.uniform_group", "topology.algebra.star" ]
[ "filter.tendsto.prod_mk_nhds", "has_sum" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83