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

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7 declarations, 0 contain sorry, 0 declared as axioms

The disjoint-clique lower bound

The red graph consists of a disjoint complete graphs of order k. A red cycle stays within one block, while an independent set uses at most one vertex from each block. This is the lower-bound construction in the proof of Theorem 1 of Cycle--clique Ramsey numbers.

  1. def OAI.CycleClique.Construction.blockGraph line 17

    Source documentation

    Disjoint red cliques: the first coordinate records the block.

    def blockGraph (a k : ℕ) : SimpleGraph (Fin a × Fin k) where
    …
  2. theorem OAI.CycleClique.Construction.blockGraph_adj line 22
  3. theorem OAI.CycleClique.Construction.cycleNext_castSucc line 25
  4. theorem OAI.CycleClique.Construction.blockGraph_cycle_bound line 31

    Source documentation

    Every red cycle in the disjoint-clique construction lies in a single block.

    theorem blockGraph_cycle_bound {a k m : ℕ} (hm : 0 < m)
        (h : HasCycle (blockGraph a k) m) : m ≤ k := by
    …

    Mentions: OAI.CycleClique.Construction.HasCycle, OAI.CycleClique.Construction.blockGraph

  5. theorem OAI.CycleClique.Construction.blockGraph_independent_bound line 50

    Source documentation

    An independent set uses at most one vertex in every block.

    theorem blockGraph_independent_bound {a k n : ℕ}
        (h : HasIndependent (blockGraph a k) n) : n ≤ a := by
    …

    Mentions: OAI.CycleClique.Construction.HasIndependent, OAI.CycleClique.Construction.blockGraph

  6. theorem OAI.CycleClique.Construction.blockGraph_not_ramsey line 60

    Source documentation

    The lower-bound coloring on a linearly labelled set of k * a vertices.

    theorem blockGraph_not_ramsey {a k m n : ℕ} (hkm : k < m) (han : a < n) :
        ¬ RamseyProperty m n (k * a) := by
    …

    Mentions: OAI.CycleClique.Construction.RamseyProperty

  7. theorem OAI.CycleClique.Construction.cycle_clique_lower_bound line 77

    Source documentation

    The sharp lower bound in the manuscript's main parameter range.

    theorem cycle_clique_lower_bound {m n : ℕ} (hm : 3 ≤ m) (hn : 3 ≤ n) :
        ¬ RamseyProperty m n ((m - 1) * (n - 1)) := by
    …

    Mentions: OAI.CycleClique.Construction.RamseyProperty