OAI/Combinatorics/Ramsey/CycleClique/Construction/LayerArithmetic.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Parity growth in the breadth-first layers

These are the two numerical contradictions in the proof of manuscript Proposition clq:layer-interface. The function p records alternating layer independence sums, whose growth contradicts their global bound.

  1. theorem OAI.CycleClique.Construction.even_layer_growth_contradiction line 15

    Source documentation

    The even-parameter layer inequalities force too much parity growth.

    theorem even_layer_growth_contradiction {s : ℕ} (_hs : 1 ≤ s) (p : ℕ → ℕ)
        (hzero : p 0 = 1) (hbound : p s ≤ 2 * s)
        (hstep : ∀ i < s,
          2 * s * p i < s * (p (i + 1) + p i - 1)) : False := by
    …
  2. theorem OAI.CycleClique.Construction.odd_layer_growth_contradiction line 36

    Source documentation

    In the odd case the final increment is at least three, rather than the usual two.

    theorem odd_layer_growth_contradiction {s : ℕ} (hs : 2 ≤ s) (p : ℕ → ℕ)
        (hzero : p 0 = 1) (hbound : p s ≤ 2 * s + 1)
        (hstep : ∀ i < s,
          (2 * s + 1) * p i ≤ s * (p (i + 1) + p i - 1)) : False := by
    …