OAI/NumberTheory/TwoPoint/Walks/BlockGeometry.lean

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12 declarations, 0 contain sorry, 0 declared as axioms

The shortest-gap argument for perfect blocks

The finite combinatorial lemma isolates a shortest gap across all prime coordinates. Every label has interval-shaped uses inside the intervening substring. The arithmetic lemmas below use exact integer displacement sums.

  1. def OAI.TwoPointCorrelations.OccurrenceIntervals line 19

    Source documentation

    Interval-shaped occurrence sets on a half-open range of positions.

    def OccurrenceIntervals {α : Type*} (P : α → ℕ → Prop) (a b : ℕ) : Prop :=
    …
  2. def OAI.TwoPointCorrelations.OccurrenceHole line 23

    Source documentation

    An occurrence gap has present endpoints and an absent interior position.

    def OccurrenceHole {α : Type*} (P : α → ℕ → Prop) (n : ℕ) (p : α) (i j : ℕ) : Prop :=
    …
  3. lemma OAI.TwoPointCorrelations.not_occurrenceIntervals_iff line 26
  4. theorem OAI.TwoPointCorrelations.exists_shortest_occurrence_hole line 42

    Source documentation

    A shortest gap has no appearances of its own label in its interior, and all labels have interval-shaped appearances before its returning endpoint.

    theorem exists_shortest_occurrence_hole {α : Type*} (P : α → ℕ → Prop) (n : ℕ)
        (h : ¬OccurrenceIntervals P 0 n) :
        ∃ p i j, OccurrenceHole P n p i j ∧
          (∀ k, i < k → k < j → ¬P p k) ∧ OccurrenceIntervals P i j := by
    …

    Mentions: OAI.TwoPointCorrelations.OccurrenceIntervals, OAI.TwoPointCorrelations.OccurrenceHole

  5. def OAI.TwoPointCorrelations.intervalDisplacement line 71

    Source documentation

    Displacement of the contiguous positions a, ..., b-1.

    def intervalDisplacement (D : ℕ → ℤ) (a b : ℕ) : ℤ := ∑ i ∈ Ico a b, D i
  6. lemma OAI.TwoPointCorrelations.intervalDisplacement_eq_sub line 73
  7. lemma OAI.TwoPointCorrelations.intervalDisplacement_cons line 77
  8. lemma OAI.TwoPointCorrelations.intervalDisplacement_singleton line 83
  9. def OAI.TwoPointCorrelations.ProhibitedInterval line 88

    Source documentation

    A concrete local prohibition, including the complete occurrence pattern and an interior suffix divisibility relation.

    def ProhibitedInterval {α : Type*} (P : α → ℕ → Prop) (D : ℕ → ℤ)
        (prime : α → ℕ) (a b : ℕ) : Prop :=
    …
  10. lemma OAI.TwoPointCorrelations.departure_difference_dvd line 96

    Source documentation

    Positivity at two departures supplies the divisibility of the intervening sum, with no assertion of independence between the sites.

    lemma departure_difference_dvd {α : Type*} (P : α → ℕ → Prop) (D : ℕ → ℤ)
        (prime : α → ℕ) (x : ℤ) (n : ℕ)
        (hpositive : ∀ p i, i < n → P p i → (prime p : ℤ) ∣ x + ∑ a ∈ range i, D a)
        {p : α} {i j : ℕ} (hij : i ≤ j) (hj : j < n) (hi : P p i) (hjP : P p j) :
        (prime p : ℤ) ∣ intervalDisplacement D i j := by
    …

    Mentions: OAI.TwoPointCorrelations.intervalDisplacement

  11. theorem OAI.TwoPointCorrelations.block_occurrence_intervals line 109

    Source documentation

    The shortest returning prime would give a prohibited subword. Thus a positive block avoiding those words has interval-shaped prime occurrences.

    theorem block_occurrence_intervals {α : Type*} (P : α → ℕ → Prop) (D : ℕ → ℤ)
        (prime : α → ℕ) (x : ℤ) (n : ℕ)
        (hpositive : ∀ p i, i < n → P p i → (prime p : ℤ) ∣ x + ∑ a ∈ range i, D a)
        (hon : ∀ p i, i < n → P p i → (prime p : ℤ) ∣ D i)
        (hoff : ∀ p i, (∃ j, j < n ∧ P p j) → i < n → ¬P p i → ¬(prime p : ℤ) ∣ D i)
        (havoid : ∀ a b, b ≤ n → ¬ProhibitedInterval P D prime a b) :
        OccurrenceIntervals P 0 n := by
    …

    Mentions: OAI.TwoPointCorrelations.ProhibitedInterval, OAI.TwoPointCorrelations.OccurrenceIntervals

  12. theorem OAI.TwoPointCorrelations.block_nonzero_subintervals line 139

    Source documentation

    Once occurrences are intervals, a directed change in the first two prime tuples supplies a prime absent from the final tuple. Any zero sum then gives the same prohibited suffix relation.

    theorem block_nonzero_subintervals {α : Type*} (P : α → ℕ → Prop) (D : ℕ → ℤ)
        (prime : α → ℕ) (n : ℕ) (hinterval : OccurrenceIntervals P 0 n)
        (hon : ∀ p i, i < n → P p i → (prime p : ℤ) ∣ D i)
        (hoff : ∀ p i, (∃ j, j < n ∧ P p j) → i < n → ¬P p i → ¬(prime p : ℤ) ∣ D i)
        (hstep : ∀ i, i < n → D i ≠ 0)
        (hchange : ∀ i, i + 1 < n → ∃ p, P p i ∧ ¬P p (i + 1))
        (havoid : ∀ a b, b ≤ n → ¬ProhibitedInterval P D prime a b) :
        ∀ a b, a < b → b ≤ n → intervalDisplacement D a b ≠ 0 := by
    …

    Mentions: OAI.TwoPointCorrelations.OccurrenceIntervals, OAI.TwoPointCorrelations.ProhibitedInterval, OAI.TwoPointCorrelations.intervalDisplacement