OAI/Combinatorics/HadwigerMatching/PairingExtension.lean

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1 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.HadwigerMatching.extend_matching_by_clique_pairs line 10

    Source documentation

    Disjoint pairs from a clique extend a touching matching when every clique vertex is adjacent to a vertex in each existing matching edge.

    theorem extend_matching_by_clique_pairs {V : Type*} [DecidableEq V]
        (G : SimpleGraph V) (E : Finset (Finset V)) (S : Finset V)
        (hE : IsTouchingMatching G E) (hS : G.IsClique (S : Set V))
        (hdisj : ∀ e ∈ E, Disjoint e S)
        (htouch : ∀ v ∈ S, ∀ e ∈ E, ∃ w ∈ e, G.Adj v w) :
        ∃ P : Finset (Finset V), IsTouchingMatching G (E ∪ P) ∧
          (E ∪ P).card = E.card + P.card ∧ S.card ≤ 2 * P.card + 1 := by
    …

    Mentions: OAI.HadwigerMatching.IsTouchingMatching