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| import OAI.Computability.WitnessedChoice.EncodedCounting | |
| namespace OAI | |
| namespace WitnessedSeparation.Grid | |
| noncomputable section | |
| open Classical Hereditary Counting HFCoding Interpretations Quantitative Filter | |
| lemma atomSizeConstant_pos : 0 < atomSizeConstant := by | |
| unfold atomSizeConstant localSizeBound | |
| positivity | |
| theorem exists_numeric_box (q : ℕ) (hq : 0 < q) (m : ℕ) : | |
| ∃ n : ℕ, 1 ≤ n ∧ | |
| let N : ℕ := atomSizeConstant*(n+1)^3 | |
| let s : ℕ := ⌈2*(n+1:ℝ)*((q:ℝ)*Real.logb 3 N)^2⌉₊ | |
| let M : ℕ := palette (n+1:ℝ) | |
| 2 ≤ N ∧ 0 < s ∧ max 4 (m+1)*s ≤ M ∧ | |
| (7:ℝ)*((max 2 m*s:ℕ):ℝ)+7*((6*((max 2 m*s:ℕ):ℝ))/boxConstant)^((3:ℝ)/2)+1 ≤ M ∧ | |
| GiantBound n M := by | |
| have hC : 0 < (atomSizeConstant:ℝ) := by exact_mod_cast atomSizeConstant_pos | |
| have hev := eventual_bounds (atomSizeConstant:ℝ) (q:ℝ) boxConstant hC boxConstant_pos m | |
| have ht : Filter.Tendsto (fun n : ℕ => (n+1:ℝ)) atTop atTop := | |
| tendsto_natCast_atTop_atTop.atTop_add tendsto_const_nhds | |
| have he := ht.eventually hev | |
| obtain ⟨n,hn,hnum⟩ := ((eventually_ge_atTop (1:ℕ)).and he).exists | |
| refine ⟨n,hn,?_⟩ | |
| dsimp only | |
| let N : ℕ := atomSizeConstant*(n+1)^3 | |
| have hN : 2 ≤ N := by | |
| have hC' : 1 ≤ atomSizeConstant := atomSizeConstant_pos | |
| have hp : 2 ≤ (n+1)^3 := by | |
| have h := Nat.pow_le_pow_left (show 2 ≤ n+1 by omega) 3 | |
| norm_num at h | |
| omega | |
| exact hp.trans (by simpa only [one_mul] using Nat.mul_le_mul_right ((n+1)^3) hC') | |
| have hlog : 0 < Real.logb 3 (N:ℝ) := Real.logb_pos (by norm_num) (by exact_mod_cast hN) | |
| have hs : 0 < ⌈2*(n+1:ℝ)*((q:ℝ)*Real.logb 3 N)^2⌉₊ := by | |
| apply Nat.ceil_pos.mpr | |
| have hq' : 0 < (q:ℝ) := by exact_mod_cast hq | |
| positivity | |
| have hrad : radius (atomSizeConstant:ℝ) (q:ℝ) (n+1:ℝ) = | |
| ⌈2*(n+1:ℝ)*((q:ℝ)*Real.logb 3 N)^2⌉₊ := by | |
| simp only [radius,N,Nat.cast_mul,Nat.cast_pow,Nat.cast_add,Nat.cast_one] | |
| rw [hrad] at hnum | |
| refine ⟨hN,hs,?_,?_,?_⟩ | |
| · exact_mod_cast hnum.1 | |
| · simpa only [N,Nat.cast_mul, Nat.cast_max, Nat.cast_ofNat] using hnum.2.1 | |
| · simpa only [GiantBound,Nat.cast_pow,Nat.cast_add,Nat.cast_one] using hnum.2.2 | |
| end | |
| end WitnessedSeparation.Grid | |
| namespace WitnessedSeparation | |
| def structureQuery (A : Interpretations.Structure Symbol) : Prop := | |
| Input.query ({ rel := A.rel } : Input A.Carrier) | |
| namespace Grid | |
| noncomputable section | |
| open Classical Hereditary Counting HFCoding Interpretations Quantitative | |
| theorem program_agrees_on_some_box (P : Program Symbol) (hP : P.polynomiallyBounded) : | |
| ∃ (n : ℕ) (_hn : 1 ≤ n) (vstar : Vertex n), | |
| P.accepts (programInput (0 : Vertex n → Scalar)) ↔ | |
| P.accepts (programInput (Pi.single vstar 1)) := by | |
| obtain ⟨c,d,hcost⟩ := hP | |
| obtain ⟨m,hm,wiδ,wiη,wiρ,wsδ,wsη,wsρ,wh,wo⟩ := P.exists_width | |
| let q := traceExponent c d | |
| have hq : 0 < q := by dsimp [q,traceExponent]; omega | |
| obtain ⟨n,hn,hnum⟩ := exists_numeric_box q hq m | |
| let N := atomSizeConstant*(n+1)^3 | |
| let B := N^timeExponent c d | |
| let vstar : Vertex n := ⟨0,0,0⟩ | |
| let S := fun i => programInput (twoCharges vstar i) | |
| have hN : 2 ≤ N := hnum.1 | |
| have hB : 2 ≤ B := (polynomial_bounds c d N hN).1 | |
| have hinput : ∀ i, Fintype.card (S i).Carrier ≤ N := | |
| fun i => (atom_card_bounds hn (twoCharges vstar i)).2 | |
| have hbInput : ∀ i, Nat.card (Atom (twoCharges vstar i)) ≤ B := by | |
| intro i | |
| apply le_trans _ (polynomial_bounds c d N hN).2.1 | |
| simpa only [Nat.card_eq_fintype_card] using hinput i | |
| have hcostB (i : Bool) : ∃ j, P.haltsAt (S i) j ∧ P.cost (S i) j ≤ B := by | |
| obtain ⟨j,hj,hc⟩ := hcost (S i) | |
| refine ⟨j,hj,hc.trans ?_⟩ | |
| calc | |
| c*(Fintype.card (S i).Carrier+1)^d ≤ c*(N+1)^d := | |
| Nat.mul_le_mul_left _ (Nat.pow_le_pow_left (Nat.add_le_add_right (hinput i) 1) d) | |
| _ ≤ B := (polynomial_bounds c d N hN).2.2.1 | |
| obtain ⟨j,hj,hjc⟩ := hcostB false | |
| obtain ⟨k,hk,hkc⟩ := hcostB true | |
| let K := min j k+1 | |
| have hK : K ≤ B := (by omega : K ≤ j+1).trans ((P.stage_le_cost (S false) j).trans hjc) | |
| have hsize : ∀ i l, l < K → Nat.card (P.state (programInput (twoCharges vstar i)) l).Carrier ≤ B := by | |
| intro i l hl | |
| cases i | |
| · exact (P.size_le_cost (S false) (by omega : l ≤ j)).trans hjc | |
| · exact (P.size_le_cost (S true) (by omega : l ≤ k)).trans hkc | |
| have hpoly : (9*B^3:ℝ) ≤ (N:ℝ)^(q:ℝ) := by | |
| simpa only [B,q,Nat.cast_pow] using real_trace_bound c d N hN | |
| have hagree (l : ℕ) (hl : l ≤ min j k) (ψ : Interpretations.Formula P.StateSymbols 0) | |
| (hw : ψ.scopedWidth < m) : | |
| ψ.holds (P.state (S false) l) ↔ ψ.holds (P.state (S true) l) := by | |
| exact stage_sentence_agrees (N := N) P vstar hn hB hK (by omega) hbInput hsize (q:ℝ) | |
| (by positivity) hpoly hm wiδ wiη wiρ wsδ wsη wsρ | |
| hnum.2.1 hnum.2.2.1 (by simpa only [N,Nat.cast_mul] using hnum.2.2.2.1) hnum.2.2.2.2 (by omega : l < K) ψ hw | |
| exact ⟨n,hn,vstar,(P.synchronize (S false) (S true) hj hk | |
| (fun l hl => hagree l hl P.halt wh) (fun l hl => hagree l hl P.output wo)).2⟩ | |
| end | |
| end Grid | |
| theorem query_not_interpretation_definable : | |
| Interpretations.NondefinableByInterpretations structureQuery := by | |
| rintro ⟨P,hpoly,hdecides⟩ | |
| obtain ⟨n,hn,vstar,hagree⟩ := Grid.program_agrees_on_some_box P hpoly | |
| obtain ⟨hzero,hunit⟩ := Grid.opposite_answers hn vstar | |
| apply hunit | |
| exact (hdecides _).mp (hagree.mp ((hdecides _).mpr hzero)) | |
| end WitnessedSeparation | |
| namespace WitnessedSeparation.Operational | |
| noncomputable section | |
| open Classical Hereditary Finset | |
| variable {A B R F : Type*} {arity : F → ℕ} | |
| local instance {C : Type*} : DecidableEq (HF C) := Classical.decEq _ | |
| abbrev empty : HF A := ordinal 0 | |
| abbrev truth : HF A := ordinal 1 | |
| def boolean (p : Prop) : HF A := if p then truth else empty | |
| @[simp] theorem truth_ne_empty : (truth : HF A) ≠ empty := | |
| fun h => by have := ordinal_injective h; omega | |
| @[simp] theorem boolean_truth (p : Prop) : boolean (A := A) p = truth ↔ p := by | |
| by_cases h : p <;> simp [boolean,h,Ne.symm truth_ne_empty] | |
| def inputRelation (rel : R → A → A → Bool) (r : R) (x y : HF A) : Prop := | |
| ∃ a b, x = atom a ∧ y = atom b ∧ rel r a b = true | |
| def allAtoms [Fintype A] : HF A := ofFinset (univ.image atom) | |
| def unionHF (x : HF A) : HF A := ofFinset ((elements x).biUnion elements) | |
| def uniqueHF (x : HF A) : HF A := | |
| if h : ∃ a, elements x = {a} then h.choose else empty | |
| lemma uniqueHF_spec (x : HF A) : | |
| (∃ a, elements x = {a} ∧ uniqueHF x = a) ∨ | |
| (¬ ∃ a, elements x = {a}) ∧ uniqueHF x = empty := by | |
| by_cases h : ∃ a, elements x = {a} | |
| · exact Or.inl ⟨h.choose,h.choose_spec,by simp only [uniqueHF,dite_eq_left h]⟩ | |
| · exact Or.inr ⟨h,by simp only [uniqueHF,dite_eq_right h]⟩ | |
| def cardinalityHF (x : HF A) : HF A := ordinal (elements x).card | |
| inductive Term (R F : Type*) (arity : F → ℕ) : ℕ → Type _ | |
| | var {k} (i : Fin k) : Term R F arity k | |
| | constant {k} (n : ℕ) : Term R F arity k | |
| | atoms {k} : Term R F arity k | |
| | app {k} (f : F) (args : Fin (arity f) → Term R F arity k) : Term R F arity k | |
| | pair {k} (a b : Term R F arity k) : Term R F arity k | |
| | union {k} (a : Term R F arity k) : Term R F arity k | |
| | unique {k} (a : Term R F arity k) : Term R F arity k | |
| | card {k} (a : Term R F arity k) : Term R F arity k | |
| | equal {k} (a b : Term R F arity k) : Term R F arity k | |
| | member {k} (a b : Term R F arity k) : Term R F arity k | |
| | isAtom {k} (a : Term R F arity k) : Term R F arity k | |
| | input {k} (r : R) (a b : Term R F arity k) : Term R F arity k | |
| | not {k} (a : Term R F arity k) : Term R F arity k | |
| | and {k} (a b : Term R F arity k) : Term R F arity k | |
| | conditional {k} (c a b : Term R F arity k) : Term R F arity k | |
| | comprehension {k} (bound : Term R F arity k) | |
| (guard body : Term R F arity (k+1)) : Term R F arity k | |
| abbrev Location (F : Type*) (arity : F → ℕ) (A : Type*) := Σ f : F, Fin (arity f) → HF A | |
| abbrev Valuation := Location F arity A → HF A | |
| structure State (F : Type*) (arity : F → ℕ) (A : Type*) where | |
| value : Location F arity A → HF A | |
| finite : Set.Finite {l | value l ≠ empty} | |
| namespace State | |
| def initial : State F arity A := ⟨fun _ => empty, by simp⟩ | |
| def support (s : State F arity A) : Finset (Location F arity A) := s.finite.toFinset | |
| @[simp] theorem mem_support (s : State F arity A) (l : Location F arity A) : | |
| l ∈ s.support ↔ s.value l ≠ empty := Set.Finite.mem_toFinset _ | |
| end State | |
| namespace Term | |
| variable [Fintype A] | |
| def eval (rel : R → A → A → Bool) (s : State F arity A) : | |
| {k : ℕ} → Term R F arity k → (Fin k → HF A) → HF A | |
| | _, .var i, v => v i | |
| | _, .constant n, _ => ordinal n | |
| | _, .atoms, _ => allAtoms | |
| | _, .app f args, v => s.value ⟨f,fun i => eval rel s (args i) v⟩ | |
| | _, .pair a b, v => double (eval rel s a v) (eval rel s b v) | |
| | _, .union a, v => unionHF (eval rel s a v) | |
| | _, .unique a, v => uniqueHF (eval rel s a v) | |
| | _, .card a, v => cardinalityHF (eval rel s a v) | |
| | _, .equal a b, v => boolean (eval rel s a v = eval rel s b v) | |
| | _, .member a b, v => boolean (eval rel s a v ∈ eval rel s b v) | |
| | _, .isAtom a, v => boolean (isSet (eval rel s a v) = false) | |
| | _, .input r a b,v => boolean (inputRelation rel r (eval rel s a v) (eval rel s b v)) | |
| | _, .not a,v => boolean (eval rel s a v ≠ truth) | |
| | _, .and a b,v => boolean (eval rel s a v = truth ∧ eval rel s b v = truth) | |
| | _, .conditional c a b,v => if eval rel s c v = truth then eval rel s a v else eval rel s b v | |
| | _, .comprehension bound guard body,v => | |
| ofFinset (((elements (eval rel s bound v)).filter | |
| (fun x => eval rel s guard (Fin.cons x v) = truth)).image | |
| (fun x => eval rel s body (Fin.cons x v))) | |
| end Term | |
| inductive Rule (R F : Type*) (arity : F → ℕ) : ℕ → Type _ | |
| | skip {k} : Rule R F arity k | |
| | update {k} (f : F) (args : Fin (arity f) → Term R F arity k) | |
| (value : Term R F arity k) : Rule R F arity k | |
| | parallel {k} (a b : Rule R F arity k) : Rule R F arity k | |
| | conditional {k} (c : Term R F arity k) (a b : Rule R F arity k) : Rule R F arity k | |
| | forall {k} (bound : Term R F arity k) (body : Rule R F arity (k+1)) : Rule R F arity k | |
| | letValue {k} (value : Term R F arity k) (body : Rule R F arity (k+1)) : Rule R F arity k | |
| abbrev Update (F : Type*) (arity : F → ℕ) (A : Type*) := Location F arity A × HF A | |
| namespace Rule | |
| variable [Fintype A] | |
| def updates (rel : R → A → A → Bool) (s : State F arity A) : | |
| {k : ℕ} → Rule R F arity k → (Fin k → HF A) → Finset (Update F arity A) | |
| | _, .skip, _ => ∅ | |
| | _, .update f args value, v => { (⟨f,fun i => (args i).eval rel s v⟩,value.eval rel s v) } | |
| | _, .parallel a b,v => updates rel s a v ∪ updates rel s b v | |
| | _, .conditional c a b,v => if c.eval rel s v = truth then updates rel s a v else updates rel s b v | |
| | _, .forall bound body,v => (elements (bound.eval rel s v)).biUnion | |
| (fun x => updates rel s body (Fin.cons x v)) | |
| | _, .letValue value body,v => updates rel s body (Fin.cons (value.eval rel s v) v) | |
| end Rule | |
| namespace State | |
| def Consistent (u : Finset (Update F arity A)) : Prop := | |
| ∀ l x y, (l,x) ∈ u → (l,y) ∈ u → x = y | |
| def updatedValue (s : State F arity A) (u : Finset (Update F arity A)) | |
| (l : Location F arity A) : HF A := | |
| if h : ∃ x, (l,x) ∈ u then h.choose else s.value l | |
| lemma updatedValue_eq (s : State F arity A) (u : Finset (Update F arity A)) | |
| (hu : Consistent u) {l : Location F arity A} {x : HF A} (hx : (l,x) ∈ u) : | |
| s.updatedValue u l = x := by | |
| have h : ∃ y, (l,y) ∈ u := ⟨x,hx⟩ | |
| simp only [updatedValue,dite_eq_left h] | |
| exact hu l _ _ h.choose_spec hx | |
| lemma updatedValue_default (s : State F arity A) (u : Finset (Update F arity A)) | |
| {l : Location F arity A} (hl : ¬ ∃ x, (l,x) ∈ u) : s.updatedValue u l = s.value l := by | |
| simp only [updatedValue,dite_eq_right hl] | |
| def applyUpdates (s : State F arity A) (u : Finset (Update F arity A)) : State F arity A where | |
| value := s.updatedValue u | |
| finite := by | |
| apply (s.finite.union (u.image Prod.fst).finite_toSet).subset | |
| intro l hl | |
| by_cases h : ∃ x, (l,x) ∈ u | |
| · obtain ⟨x,hx⟩ := h | |
| exact Or.inr (mem_image.mpr ⟨(l,x),hx,rfl⟩) | |
| · exact Or.inl (by simpa only [Set.mem_ofPred_eq,updatedValue,dite_eq_right h] using hl) | |
| end State | |
| inductive Control | halt | accept deriving DecidableEq | |
| instance : Fintype Control where | |
| elems := {.halt,.accept} | |
| complete := by intro x; cases x <;> simp | |
| structure Machine (R : Type*) where | |
| Functions : Type | |
| finiteFunctions : Fintype Functions | |
| arity : Functions → ℕ | |
| rule : Rule R (Control ⊕ Functions) (Sum.elim (fun _ => 0) arity) 0 | |
| namespace Machine | |
| variable (P : Machine R) [Fintype A] | |
| abbrev functionArity : Control ⊕ P.Functions → ℕ := Sum.elim (fun _ => 0) P.arity | |
| abbrev Store := State (Control ⊕ P.Functions) P.functionArity A | |
| def flag (s : P.Store (A := A)) (c : Control) : Prop := s.value ⟨.inl c,Fin.elim0⟩ = truth | |
| def step (rel : R → A → A → Bool) (s : P.Store (A := A)) : Option (P.Store (A := A)) := | |
| if P.flag s .halt then some s else | |
| let u := P.rule.updates rel s Fin.elim0 | |
| if State.Consistent u then some (s.applyUpdates u) else none | |
| def run (rel : R → A → A → Bool) : ℕ → Option (P.Store (A := A)) | |
| | 0 => some State.initial | |
| | j+1 => (run rel j).bind (P.step rel) | |
| def accepts (rel : R → A → A → Bool) : Prop := | |
| ∃ h s, P.run rel h = some s ∧ P.flag s .halt ∧ P.flag s .accept | |
| end Machine | |
| end | |
| end WitnessedSeparation.Operational | |
| namespace WitnessedSeparation.Hereditary | |
| noncomputable section | |
| open Classical Finset | |
| variable {A B : Type*} | |
| local instance {C : Type*} : DecidableEq (HF C) := Classical.decEq _ | |
| lemma mem_mapEquiv (e : A ≃ B) (x y : HF A) : map e x ∈ map e y ↔ x ∈ y := by | |
| change map e x ∈ elements (map e y) ↔ x ∈ elements y | |
| rw [elements_map] | |
| constructor | |
| · intro h | |
| obtain ⟨z,hz,he⟩ := Finset.mem_image.mp h | |
| exact (mapEquiv e).injective he ▸ hz | |
| · intro h | |
| exact Finset.mem_image.mpr ⟨x,h,rfl⟩ | |
| lemma rtc_map (e : A ≃ B) {x y : HF A} | |
| (h : Relation.ReflTransGen (fun a b : HF A => a ∈ b) x y) : | |
| Relation.ReflTransGen (fun a b : HF B => a ∈ b) (map e x) (map e y) := by | |
| induction h with | |
| | refl => exact .refl | |
| | tail hab hbc ih => exact ih.tail ((mem_mapEquiv e _ _).mpr hbc) | |
| lemma closure_map (e : A ≃ B) (x : HF A) : closure (map e x) = (closure x).image (map e) := by | |
| ext y | |
| obtain ⟨z,rfl⟩ := (mapEquiv e).surjective y | |
| rw [mem_closure_iff,mem_image] | |
| constructor | |
| · intro h | |
| have h' : Relation.ReflTransGen (fun a b : HF A => a ∈ b) z x := by | |
| have hm := rtc_map e.symm h | |
| change Relation.ReflTransGen (fun a b : HF A => a ∈ b) | |
| ((mapEquiv e).symm ((mapEquiv e) z)) ((mapEquiv e).symm ((mapEquiv e) x)) at hm | |
| simpa only [Equiv.symm_apply_apply] using hm | |
| exact ⟨z,(mem_closure_iff z x).mpr h',rfl⟩ | |
| · rintro ⟨w,hw,he⟩ | |
| have h := (mem_closure_iff w x).mp hw | |
| have hm := rtc_map e h | |
| exact he ▸ hm | |
| def familyClosure (f : Finset (HF A)) : Finset (HF A) := f.biUnion closure | |
| lemma mem_familyClosure {f : Finset (HF A)} {x : HF A} : | |
| x ∈ familyClosure f ↔ ∃ y ∈ f, x ∈ closure y := by simp [familyClosure] | |
| lemma familyClosure_contains {f : Finset (HF A)} {x : HF A} (hx : x ∈ f) : | |
| x ∈ familyClosure f := mem_familyClosure.mpr ⟨x,hx,mem_closure_self x⟩ | |
| lemma familyClosure_transitive {f : Finset (HF A)} {x y : HF A} | |
| (hx : x ∈ familyClosure f) (hy : y ∈ x) : y ∈ familyClosure f := by | |
| obtain ⟨z,hz,hxz⟩ := mem_familyClosure.mp hx | |
| exact mem_familyClosure.mpr ⟨z,hz,closure_transitive hxz hy⟩ | |
| end | |
| end WitnessedSeparation.Hereditary | |
| namespace WitnessedSeparation.Operational | |
| noncomputable section | |
| open Classical Hereditary Finset | |
| variable {A R F : Type*} {arity : F → ℕ} | |
| local instance {C : Type*} : DecidableEq (HF C) := Classical.decEq _ | |
| namespace State | |
| def critical (s : State F arity A) : Finset (HF A) := | |
| s.support.biUnion (fun l => insert (s.value l) (univ.image l.2)) | |
| lemma value_mem_critical (s : State F arity A) {l : Location F arity A} | |
| (h : s.value l ≠ empty) : s.value l ∈ s.critical := by | |
| exact mem_biUnion.mpr ⟨l,(mem_support s l).mpr h,mem_insert_self _ _⟩ | |
| lemma argument_mem_critical (s : State F arity A) {l : Location F arity A} | |
| (h : s.value l ≠ empty) (i : Fin (arity l.1)) : l.2 i ∈ s.critical := by | |
| exact mem_biUnion.mpr ⟨l,(mem_support s l).mpr h,mem_insert_of_mem (mem_image.mpr ⟨i,mem_univ _,rfl⟩)⟩ | |
| def active [Fintype A] (s : State F arity A) : Finset (HF A) := | |
| familyClosure (s.critical ∪ {allAtoms,empty,truth} ∪ univ.image atom) | |
| lemma active_transitive [Fintype A] (s : State F arity A) {x y : HF A} | |
| (hx : x ∈ s.active) (hy : y ∈ x) : y ∈ s.active := | |
| familyClosure_transitive hx hy | |
| end State | |
| namespace Machine | |
| variable (P : Machine R) [Fintype A] | |
| def runActive (rel : R → A → A → Bool) (h : ℕ) : Finset (HF A) := | |
| (range (h+1)).biUnion fun j => match P.run rel j with | |
| | none => ∅ | |
| | some s => s.active | |
| lemma state_active_subset (rel : R → A → A → Bool) {h j : ℕ} {s : P.Store (A := A)} | |
| (hj : j ≤ h) (hs : P.run rel j = some s) : s.active ⊆ P.runActive rel h := by | |
| intro x hx | |
| exact mem_biUnion.mpr ⟨j,by simpa using hj,by simpa only [hs] using hx⟩ | |
| lemma runActive_transitive (rel : R → A → A → Bool) (h : ℕ) {x y : HF A} | |
| (hx : x ∈ P.runActive rel h) (hy : y ∈ x) : y ∈ P.runActive rel h := by | |
| obtain ⟨j,hj,hx⟩ := mem_biUnion.mp hx | |
| cases hs : P.run rel j with | |
| | none => simp only [hs,Finset.notMem_empty] at hx | |
| | some s => | |
| simp only [hs] at hx | |
| exact mem_biUnion.mpr ⟨j,hj,by simpa only [hs] using s.active_transitive hx hy⟩ | |
| lemma runActive_card_le (rel : R → A → A → Bool) (h K : ℕ) | |
| (hb : ∀ j ≤ h, ∀ s, P.run rel j = some s → s.active.card ≤ K) : | |
| (P.runActive rel h).card ≤ (h+1)*K := by | |
| unfold runActive | |
| apply (card_biUnion_le).trans | |
| calc | |
| (∑ j ∈ range (h+1), (match P.run rel j with | none => ∅ | some s => s.active).card) ≤ | |
| ∑ _j ∈ range (h+1), K := by | |
| apply sum_le_sum | |
| intro j hj | |
| cases hs : P.run rel j with | |
| | none => simp | |
| | some s => exact hb j (by simpa using hj) s hs | |
| _ = (h+1)*K := by simp | |
| def PolynomiallyBounded (P : Machine R) : Prop := | |
| ∃ c d : ℕ, ∀ (A : Type) (aFinite : Fintype A) (rel : R → A → A → Bool), | |
| ∃ h s, @Machine.run A R P aFinite rel h = some s ∧ | |
| P.flag s .halt ∧ h+(P.runActive rel h).card ≤ c*(Fintype.card A+1)^d | |
| end Machine | |
| end | |
| noncomputable section | |
| open Classical Hereditary Finset | |
| variable {A B R F : Type*} {arity : F → ℕ} | |
| local instance {C : Type*} : DecidableEq (HF C) := Classical.decEq _ | |
| abbrev lift (e : A ≃ B) : HF A ≃ HF B := mapEquiv e | |
| @[simp] lemma lift_empty (e : A ≃ B) : lift e empty = empty := map_ordinal e 0 | |
| @[simp] lemma lift_truth (e : A ≃ B) : lift e truth = truth := map_ordinal e 1 | |
| @[simp] lemma lift_ordinal (e : A ≃ B) (n : ℕ) : lift e (ordinal n) = ordinal n := map_ordinal e n | |
| @[simp] lemma lift_double (e : A ≃ B) (x y : HF A) : lift e (double x y) = double (lift e x) (lift e y) := map_double e x y | |
| @[simp] lemma lift_isSet (e : A ≃ B) (x : HF A) : isSet (lift e x) = isSet x := isSet_map e x | |
| @[simp] lemma lift_boolean (e : A ≃ B) (p : Prop) : lift e (boolean p) = boolean p := by | |
| by_cases h : p <;> simp [boolean,h] | |
| @[simp] lemma lift_truth_iff (e : A ≃ B) (x : HF A) : lift e x = truth ↔ x = truth := by | |
| rw [← lift_truth e,Equiv.apply_eq_iff_eq] | |
| @[simp] lemma lift_empty_iff (e : A ≃ B) (x : HF A) : lift e x = empty ↔ x = empty := by | |
| rw [← lift_empty e,Equiv.apply_eq_iff_eq] | |
| @[simp] lemma lift_mem_iff (e : A ≃ B) (x y : HF A) : lift e x ∈ lift e y ↔ x ∈ y := mem_mapEquiv e x y | |
| lemma lift_elements (e : A ≃ B) (x : HF A) : elements (lift e x) = (elements x).image (lift e) := elements_map e x | |
| lemma lift_ofFinset (e : A ≃ B) (s : Finset (HF A)) : lift e (ofFinset s) = ofFinset (s.image (lift e)) := map_ofFinset e s | |
| lemma lift_allAtoms [Fintype A] [Fintype B] (e : A ≃ B) : lift e allAtoms = allAtoms := by | |
| rw [allAtoms,lift_ofFinset,allAtoms] | |
| congr 1 | |
| ext x | |
| simp only [mem_image,mem_univ,true_and] | |
| constructor | |
| · rintro ⟨y,⟨a,rfl⟩,rfl⟩ | |
| exact ⟨e a,rfl⟩ | |
| · rintro ⟨b,rfl⟩ | |
| exact ⟨atom (e.symm b),⟨e.symm b,rfl⟩,by simp [lift,mapEquiv]⟩ | |
| lemma lift_union (e : A ≃ B) (x : HF A) : lift e (unionHF x) = unionHF (lift e x) := by | |
| rw [unionHF,lift_ofFinset,unionHF,lift_elements] | |
| congr 1 | |
| ext z | |
| simp only [mem_image,mem_biUnion] | |
| constructor | |
| · rintro ⟨z,⟨y,hy,hz⟩,rfl⟩ | |
| exact ⟨lift e y,⟨y,hy,rfl⟩,(lift_mem_iff e z y).mpr hz⟩ | |
| · rintro ⟨y,⟨w,hw,rfl⟩,hz⟩ | |
| refine ⟨(lift e).symm z,⟨w,hw,?_⟩,Equiv.apply_symm_apply _ _⟩ | |
| have := (lift_mem_iff e ((lift e).symm z) w).mp | |
| apply this | |
| simpa only [Equiv.apply_symm_apply] using (show z ∈ lift e w from hz) | |
| lemma lift_unique (e : A ≃ B) (x : HF A) : lift e (uniqueHF x) = uniqueHF (lift e x) := by | |
| rcases uniqueHF_spec x with ⟨a,ha,hu⟩ | ⟨ha,hu⟩ | |
| · have h : elements (lift e x) = {lift e a} := by rw [lift_elements,ha,image_singleton] | |
| rcases uniqueHF_spec (lift e x) with ⟨b,hb,hv⟩ | ⟨hb,hv⟩ | |
| · rw [hu,hv] | |
| exact singleton_injective (h.symm.trans hb) | |
| · exact (hb ⟨_,h⟩).elim | |
| · rcases uniqueHF_spec (lift e x) with ⟨b,hb,hv⟩ | ⟨hb,hv⟩ | |
| · exfalso | |
| apply ha | |
| refine ⟨(lift e).symm b,?_⟩ | |
| apply (image_injective (lift e).injective) | |
| rw [← lift_elements,hb,image_singleton,Equiv.apply_symm_apply] | |
| · rw [hu,hv,lift_empty] | |
| lemma lift_card (e : A ≃ B) (x : HF A) : lift e (cardinalityHF x) = cardinalityHF (lift e x) := by | |
| simp only [cardinalityHF,lift_ordinal,lift_elements,card_image_of_injective _ (lift e).injective] | |
| lemma lift_input (e : A ≃ B) (rel : R → A → A → Bool) (rel' : R → B → B → Bool) | |
| (hrel : ∀ r a b, rel' r (e a) (e b) = rel r a b) (r : R) (x y : HF A) : | |
| inputRelation rel' r (lift e x) (lift e y) ↔ inputRelation rel r x y := by | |
| constructor | |
| · rintro ⟨a,b,ha,hb,hr⟩ | |
| refine ⟨e.symm a,e.symm b,?_,?_,?_⟩ | |
| · apply (lift e).injective | |
| simpa [lift,mapEquiv] using ha | |
| · apply (lift e).injective | |
| simpa [lift,mapEquiv] using hb | |
| · simpa only [← hrel,Equiv.apply_symm_apply] using hr | |
| · rintro ⟨a,b,rfl,rfl,hr⟩ | |
| exact ⟨e a,e b,rfl,rfl,by rw [hrel]; exact hr⟩ | |
| def locationEquiv (e : A ≃ B) : Location F arity A ≃ Location F arity B := | |
| Equiv.sigmaCongrRight (fun _ => Equiv.piCongrRight (fun _ => lift e)) | |
| @[simp] lemma locationEquiv_apply (e : A ≃ B) (f : F) (v : Fin (arity f) → HF A) : | |
| locationEquiv e ⟨f,v⟩ = ⟨f,fun j => lift e (v j)⟩ := rfl | |
| @[simp] lemma locationEquiv_symm_apply (e : A ≃ B) (f : F) (v : Fin (arity f) → HF B) : | |
| (locationEquiv e).symm ⟨f,v⟩ = ⟨f,fun j => (lift e).symm (v j)⟩ := rfl | |
| namespace State | |
| def transport (e : A ≃ B) (s : State F arity A) : State F arity B where | |
| value := fun l => lift e (s.value ((locationEquiv e).symm l)) | |
| finite := by | |
| apply (s.finite.image (locationEquiv e)).subset | |
| intro l hl | |
| exact ⟨(locationEquiv e).symm l,by simpa using hl,Equiv.apply_symm_apply _ _⟩ | |
| @[simp] lemma transport_value (e : A ≃ B) (s : State F arity A) (l : Location F arity A) : | |
| (s.transport e).value (locationEquiv e l) = lift e (s.value l) := by | |
| simp [transport] | |
| @[ext] lemma ext_value (s t : State F arity A) (h : ∀ l, s.value l = t.value l) : s = t := by | |
| cases s; cases t | |
| congr | |
| funext l | |
| exact h l | |
| @[simp] lemma transport_initial (e : A ≃ B) : (initial : State F arity A).transport e = initial := by | |
| apply ext_value | |
| intro l | |
| simp [transport,initial] | |
| end State | |
| namespace Term | |
| variable [Fintype A] [Fintype B] | |
| lemma eval_transport (e : A ≃ B) (rel : R → A → A → Bool) (rel' : R → B → B → Bool) | |
| (hrel : ∀ r a b, rel' r (e a) (e b) = rel r a b) (s : State F arity A) | |
| {k : ℕ} (t : Term R F arity k) (v : Fin k → HF A) : | |
| t.eval rel' (s.transport e) (fun j => lift e (v j)) = lift e (t.eval rel s v) := by | |
| induction t with | |
| | var i => rfl | |
| | constant n => simp [eval] | |
| | atoms => simp [eval,lift_allAtoms] | |
| | app f args ih => | |
| simp only [eval,ih] | |
| exact s.transport_value e ⟨f,fun j => (args j).eval rel s v⟩ | |
| | pair a b ia ib => simp only [eval,ia,ib,lift_double] | |
| | union a ia => simp only [eval,ia,lift_union] | |
| | unique a ia => simp only [eval,ia,lift_unique] | |
| | card a ia => simp only [eval,ia,lift_card] | |
| | equal a b ia ib => simp only [eval,ia,ib,Equiv.apply_eq_iff_eq,lift_boolean] | |
| | member a b ia ib => simp only [eval,ia,ib,lift_mem_iff,lift_boolean] | |
| | isAtom a ia => simp only [eval,ia,lift_isSet,lift_boolean] | |
| | input r a b ia ib => simp only [eval,ia,ib,lift_input e rel rel' hrel,lift_boolean] | |
| | not a ia => simp only [eval,ia,ne_eq,lift_truth_iff,lift_boolean] | |
| | and a b ia ib => simp only [eval,ia,ib,lift_truth_iff,lift_boolean] | |
| | conditional c a b ic ia ib => | |
| simp only [eval,ic,lift_truth_iff] | |
| split <;> simp_all | |
| | comprehension bound guard body ihb ihg iht => | |
| simp only [eval,ihb,lift_elements,lift_ofFinset] | |
| congr 1 | |
| ext z | |
| simp only [mem_image,mem_filter] | |
| constructor | |
| · rintro ⟨z,⟨⟨x,hx,rfl⟩,hg⟩,hz⟩ | |
| have hh : (lift e) ∘ (Fin.cons x v) = Fin.cons (lift e x) (fun j => lift e (v j)) := by | |
| funext j; refine Fin.cases rfl (fun _ => rfl) j | |
| dsimp only [Function.comp_def] at hh | |
| rw [← hh,ihg,lift_truth_iff] at hg | |
| rw [← hh,iht] at hz | |
| exact ⟨body.eval rel s (Fin.cons x v),⟨x,⟨hx,hg⟩,rfl⟩,hz⟩ | |
| · rintro ⟨z,⟨x,⟨hx,hg⟩,rfl⟩,hz⟩ | |
| have hh : (lift e) ∘ (Fin.cons x v) = Fin.cons (lift e x) (fun j => lift e (v j)) := by | |
| funext j; refine Fin.cases rfl (fun _ => rfl) j | |
| dsimp only [Function.comp_def] at hh | |
| exact ⟨lift e x,⟨⟨x,hx,rfl⟩,by rw [← hh,ihg,lift_truth_iff]; exact hg⟩, | |
| by rw [← hh,iht]; exact hz⟩ | |
| end Term | |
| abbrev updateEquiv (e : A ≃ B) : Update F arity A ≃ Update F arity B := | |
| Equiv.prodCongr (locationEquiv e) (lift e) | |
| lemma mem_update_image (e : A ≃ B) (u : Finset (Update F arity A)) | |
| (l : Location F arity A) (x : HF A) : | |
| (locationEquiv e l,lift e x) ∈ u.image (updateEquiv e) ↔ (l,x) ∈ u := by | |
| change updateEquiv e (l,x) ∈ _ ↔ _ | |
| simp only [mem_image,Equiv.apply_eq_iff_eq,exists_eq_right] | |
| namespace Rule | |
| variable [Fintype A] [Fintype B] | |
| lemma updates_transport (e : A ≃ B) (rel : R → A → A → Bool) (rel' : R → B → B → Bool) | |
| (hrel : ∀ r a b, rel' r (e a) (e b) = rel r a b) (s : State F arity A) | |
| {k : ℕ} (r : Rule R F arity k) (v : Fin k → HF A) : | |
| r.updates rel' (s.transport e) (fun j => lift e (v j)) = | |
| (r.updates rel s v).image (updateEquiv e) := by | |
| induction r with | |
| | skip => simp [updates] | |
| | update f args value => | |
| simp only [updates,Term.eval_transport e rel rel' hrel,image_singleton] | |
| rfl | |
| | parallel a b ia ib => | |
| simp only [updates,ia,ib,image_union] | |
| | conditional c a b ia ib => | |
| simp only [updates,Term.eval_transport e rel rel' hrel,lift_truth_iff] | |
| split <;> simp_all | |
| | «forall» bound body ih => | |
| simp only [updates,Term.eval_transport e rel rel' hrel,lift_elements] | |
| rw [biUnion_image,image_biUnion] | |
| apply biUnion_congr rfl | |
| intro x hx | |
| have hcons : (lift e) ∘ Fin.cons x v = Fin.cons (lift e x) (fun j => lift e (v j)) := by | |
| funext j; refine Fin.cases rfl (fun _ => rfl) j | |
| dsimp only [Function.comp_def] at hcons | |
| rw [← hcons,ih] | |
| | letValue value body ih => | |
| simp only [updates,Term.eval_transport e rel rel' hrel] | |
| have hcons : (lift e) ∘ Fin.cons (value.eval rel s v) v = | |
| Fin.cons (lift e (value.eval rel s v)) (fun j => lift e (v j)) := by | |
| funext j; refine Fin.cases rfl (fun _ => rfl) j | |
| dsimp only [Function.comp_def] at hcons | |
| rw [← hcons,ih] | |
| end Rule | |
| namespace State | |
| lemma consistent_transport (e : A ≃ B) (u : Finset (Update F arity A)) : | |
| Consistent (u.image (updateEquiv e)) ↔ Consistent u := by | |
| constructor | |
| · intro h l x y hx hy | |
| apply (lift e).injective | |
| exact h _ _ _ ((mem_update_image e u l x).mpr hx) ((mem_update_image e u l y).mpr hy) | |
| · intro h l x y hx hy | |
| obtain ⟨l,rfl⟩ := (locationEquiv e).surjective l | |
| obtain ⟨x,rfl⟩ := (lift e).surjective x | |
| obtain ⟨y,rfl⟩ := (lift e).surjective y | |
| exact congrArg (lift e) (h _ _ _ ((mem_update_image e u l x).mp hx) | |
| ((mem_update_image e u l y).mp hy)) | |
| lemma applyUpdates_transport (e : A ≃ B) (s : State F arity A) | |
| (u : Finset (Update F arity A)) (hu : Consistent u) : | |
| (s.transport e).applyUpdates (u.image (updateEquiv e)) = (s.applyUpdates u).transport e := by | |
| apply ext_value | |
| intro l | |
| obtain ⟨l,rfl⟩ := (locationEquiv e).surjective l | |
| rw [transport_value] | |
| change (s.transport e).updatedValue (u.image (updateEquiv e)) (locationEquiv e l) = | |
| lift e (s.updatedValue u l) | |
| by_cases h : ∃ x, (l,x) ∈ u | |
| · obtain ⟨x,hx⟩ := h | |
| rw [s.updatedValue_eq u hu hx, | |
| updatedValue_eq _ _ ((consistent_transport e u).mpr hu) ((mem_update_image e u l x).mpr hx)] | |
| · rw [s.updatedValue_default u h,updatedValue_default] | |
| · exact s.transport_value e l | |
| · rintro ⟨x,hx⟩ | |
| obtain ⟨x,rfl⟩ := (lift e).surjective x | |
| exact h ⟨x,(mem_update_image e u l x).mp hx⟩ | |
| lemma support_transport (e : A ≃ B) (s : State F arity A) : | |
| (s.transport e).support = s.support.image (locationEquiv e) := by | |
| ext l | |
| obtain ⟨l,rfl⟩ := (locationEquiv e).surjective l | |
| simp only [mem_image,Equiv.apply_eq_iff_eq,exists_eq_right,mem_support,transport_value,ne_eq,lift_empty_iff] | |
| lemma critical_transport (e : A ≃ B) (s : State F arity A) : | |
| (s.transport e).critical = s.critical.image (lift e) := by | |
| simp only [critical,support_transport,biUnion_image,image_biUnion] | |
| apply biUnion_congr rfl | |
| intro l hl | |
| rw [transport_value,image_insert,image_image] | |
| cases l | |
| rfl | |
| lemma active_transport [Fintype A] [Fintype B] (e : A ≃ B) (s : State F arity A) : | |
| (s.transport e).active = s.active.image (lift e) := by | |
| have hf : ∀ f : Finset (HF A), familyClosure (f.image (lift e)) = (familyClosure f).image (lift e) := by | |
| intro f | |
| simp only [familyClosure,biUnion_image,image_biUnion] | |
| apply biUnion_congr rfl | |
| intro x hx | |
| exact closure_map e x | |
| have ha : (univ.image (@atom B)).image ((lift e).symm) = univ.image (@atom A) := by | |
| ext x | |
| simp only [mem_image,mem_univ,true_and] | |
| constructor | |
| · rintro ⟨_,⟨b,rfl⟩,rfl⟩ | |
| exact ⟨e.symm b,rfl⟩ | |
| · rintro ⟨a,rfl⟩ | |
| exact ⟨atom (e a),⟨e a,rfl⟩,by simp [lift,mapEquiv]⟩ | |
| have ha' : univ.image (@atom B) = (univ.image (@atom A)).image (lift e) := by | |
| rw [← ha,image_image] | |
| simp only [Function.comp_def,Equiv.apply_symm_apply,image_id'] | |
| unfold active | |
| rw [critical_transport,ha',← hf] | |
| congr 1 | |
| simp only [image_union,image_insert,image_singleton,lift_allAtoms,lift_empty,lift_truth] | |
| end State | |
| namespace Machine | |
| variable (P : Machine R) [Fintype A] [Fintype B] | |
| omit [Fintype A] [Fintype B] in | |
| lemma flag_transport (e : A ≃ B) (s : P.Store (A := A)) (c : Control) : | |
| P.flag (s.transport e) c ↔ P.flag s c := by | |
| have h : locationEquiv e (⟨Sum.inl c,Fin.elim0⟩ : Location _ P.functionArity A) = | |
| ⟨Sum.inl c,Fin.elim0⟩ := by | |
| change (⟨Sum.inl c,fun j : Fin 0 => lift e (Fin.elim0 j : HF A)⟩ : Location _ P.functionArity B) = ⟨Sum.inl c,Fin.elim0⟩ | |
| congr 1 | |
| funext i | |
| exact Fin.elim0 i | |
| unfold flag | |
| rw [← h,State.transport_value,lift_truth_iff] | |
| lemma step_transport (e : A ≃ B) (rel : R → A → A → Bool) (rel' : R → B → B → Bool) | |
| (hrel : ∀ r a b, rel' r (e a) (e b) = rel r a b) (s : P.Store (A := A)) : | |
| P.step rel' (s.transport e) = (P.step rel s).map (State.transport e) := by | |
| have hv : (fun j : Fin 0 => lift e (Fin.elim0 j : HF A)) = Fin.elim0 := by | |
| funext j; exact Fin.elim0 j | |
| have hu := P.rule.updates_transport e rel rel' hrel s Fin.elim0 | |
| rw [hv] at hu | |
| simp only [step,flag_transport,hu,State.consistent_transport] | |
| split | |
| · rfl | |
| · split | |
| · rename_i hc | |
| simp only [Option.map_some] | |
| congr 1 | |
| exact State.applyUpdates_transport e s _ hc | |
| · rfl | |
| lemma run_transport (e : A ≃ B) (rel : R → A → A → Bool) (rel' : R → B → B → Bool) | |
| (hrel : ∀ r a b, rel' r (e a) (e b) = rel r a b) (j : ℕ) : | |
| P.run rel' j = (P.run rel j).map (State.transport e) := by | |
| induction j with | |
| | zero => simp [run] | |
| | succ j ih => | |
| simp only [run,ih] | |
| cases hs : P.run rel j with | |
| | none => rfl | |
| | some s => exact P.step_transport e rel rel' hrel s | |
| lemma runActive_transport (e : A ≃ B) (rel : R → A → A → Bool) (rel' : R → B → B → Bool) | |
| (hrel : ∀ r a b, rel' r (e a) (e b) = rel r a b) (h : ℕ) : | |
| P.runActive rel' h = (P.runActive rel h).image (lift e) := by | |
| unfold runActive | |
| rw [biUnion_image] | |
| apply biUnion_congr rfl | |
| intro j hj | |
| rw [P.run_transport e rel rel' hrel] | |
| cases hs : P.run rel j with | |
| | none => simp | |
| | some s => exact s.active_transport e | |
| end Machine | |
| end | |
| end WitnessedSeparation.Operational | |
| namespace WitnessedSeparation.Hereditary | |
| noncomputable section | |
| open Classical Finset | |
| variable {A : Type*} | |
| local instance {C : Type*} : DecidableEq (HF C) := Classical.decEq _ | |
| lemma closure_ofFinset (s : Finset (HF A)) : | |
| closure (ofFinset s) = insert (ofFinset s) (familyClosure s) := by | |
| rw [closure,elements_ofFinset] | |
| congr 1 | |
| ext x | |
| simp [familyClosure] | |
| lemma closure_subset_of_transitive {s : Finset (HF A)} | |
| (hs : ∀ x ∈ s, ∀ y, y ∈ x → y ∈ s) {x : HF A} (hx : x ∈ s) : closure x ⊆ s := by | |
| intro y hy | |
| have h := (mem_closure_iff y x).mp hy | |
| clear hy | |
| induction h with | |
| | refl => exact hx | |
| | @tail b c h hbc ih => exact ih (hs c hx b hbc) | |
| lemma elements_subset_closure (x : HF A) : elements x ⊆ closure x := by | |
| intro y hy | |
| exact closure_member_subset hy (mem_closure_self y) | |
| lemma closure_atom (a : A) : closure (atom a) = {atom a} := by | |
| rw [closure,elements_atom] | |
| simp | |
| lemma closure_double_subset (x y : HF A) : | |
| closure (double x y) ⊆ insert (double x y) (closure x ∪ closure y) := by | |
| rw [double,closure_ofFinset] | |
| intro z hz | |
| simp only [mem_insert,mem_union] at hz ⊢ | |
| rcases hz with h | h | |
| · exact Or.inl h | |
| · obtain ⟨w,hw,hz⟩ := mem_familyClosure.mp h | |
| have he : w = x ∨ w = y := by simpa only [Finset.mem_insert,Finset.mem_singleton] using hw | |
| rcases he with he | he | |
| · rw [he] at hz; exact Or.inr (Or.inl hz) | |
| · rw [he] at hz; exact Or.inr (Or.inr hz) | |
| lemma closure_ordinal (n : ℕ) : closure (ordinal (A := A) n) = (range (n+1)).image ordinal := by | |
| induction n using Nat.strong_induction_on with | |
| | h n ih => | |
| rw [closure] | |
| ext x | |
| simp only [mem_insert,mem_biUnion,mem_attach,true_and,Subtype.exists,mem_image,mem_range] | |
| constructor | |
| · rintro (rfl | ⟨y,hy,hx⟩) | |
| · exact ⟨n,by omega,rfl⟩ | |
| · obtain ⟨j,hj,rfl⟩ := (mem_ordinal y n).mp hy | |
| rw [ih j hj] at hx | |
| obtain ⟨k,hk,rfl⟩ := mem_image.mp hx | |
| exact ⟨k,by simp only [mem_range] at hk; omega,rfl⟩ | |
| · rintro ⟨j,hj,rfl⟩ | |
| by_cases he : j = n | |
| · exact Or.inl (by rw [he]) | |
| · exact Or.inr ⟨ordinal j,(mem_ordinal _ _).mpr ⟨j,by omega,rfl⟩,mem_closure_self _⟩ | |
| lemma card_closure_ordinal (n : ℕ) : (closure (ordinal (A := A) n)).card = n+1 := by | |
| rw [closure_ordinal,card_image_of_injective _ (fun _ _ h => ordinal_injective h),card_range] | |
| end | |
| end WitnessedSeparation.Hereditary | |
| end OAI | |