OAI/Combinatorics/HadwigerMatching/BasicMatching.lean
6 declarations, 0 contain sorry, 0 declared as axioms
- theorem
OAI.HadwigerMatching.isTouchingMatching_emptyline 14Source documentation
The empty family is a touching matching.
theorem isTouchingMatching_empty (G : SimpleGraph V) : IsTouchingMatching G ∅ := by …Mentions: OAI.HadwigerMatching.IsTouchingMatching
- theorem
OAI.HadwigerMatching.IsTouchingMatching.sum_card_eqline 19Source documentation
Every member contributes exactly two vertices.
theorem IsTouchingMatching.sum_card_eq {M : Finset (Finset V)} (hM : IsTouchingMatching G M) : (∑ e ∈ M, e.card) = 2 * M.card := by …Mentions: OAI.HadwigerMatching.IsTouchingMatching
- theorem
OAI.HadwigerMatching.IsTouchingMatching.two_mul_card_leline 26Source documentation
Disjointness bounds twice the number of matching edges by the graph order.
theorem IsTouchingMatching.two_mul_card_le [Fintype V] {M : Finset (Finset V)} (hM : IsTouchingMatching G M) : 2 * M.card ≤ Fintype.card V := by …Mentions: OAI.HadwigerMatching.IsTouchingMatching
- theorem
OAI.HadwigerMatching.connectedMatchingNumber_bddAboveline 40Source documentation
Touching matching cardinalities are bounded on a finite vertex type.
theorem connectedMatchingNumber_bddAbove [Fintype V] (G : SimpleGraph V) : BddAbove {n : ℕ | ∃ M : Finset (Finset V), IsTouchingMatching G M ∧ M.card = n} := by …Mentions: OAI.HadwigerMatching.IsTouchingMatching
- theorem
OAI.HadwigerMatching.matching_card_le_numberline 50Source documentation
Every touching matching is bounded by the connected matching number.
theorem matching_card_le_number [Fintype V] {M : Finset (Finset V)} (hM : IsTouchingMatching G M) : M.card ≤ connectedMatchingNumber G := by …Mentions: OAI.HadwigerMatching.IsTouchingMatching, OAI.HadwigerMatching.connectedMatchingNumber
- theorem
OAI.HadwigerMatching.exists_matching_card_eq_numberline 55Source documentation
The connected matching number is realized by a touching matching.
theorem exists_matching_card_eq_number [Fintype V] (G : SimpleGraph V) : ∃ M : Finset (Finset V), IsTouchingMatching G M ∧ M.card = connectedMatchingNumber G := by …Mentions: OAI.HadwigerMatching.IsTouchingMatching, OAI.HadwigerMatching.connectedMatchingNumber