OAI/Combinatorics/GraphThreshold/GraphSupport.lean

GitHub source file

14 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.LeanBlast.SecondKahnKalai.edgeSubgraph line 15

    Source documentation

    The subgraph containing exactly the given edges and their incident vertices. For the empty edge set this has no vertices, as required for internal copies.

    def edgeSubgraph (S : Finset (Edge n)) : (⊤ : SimpleGraph (Fin n)).Subgraph where
    …

    Mentions: OAI.LeanBlast.SecondKahnKalai.Edge

  2. def OAI.LeanBlast.SecondKahnKalai.edgeSupportGraph line 22
  3. theorem OAI.LeanBlast.SecondKahnKalai.edgeSubgraph_spanningCoe line 26
  4. theorem OAI.LeanBlast.SecondKahnKalai.edgeSupportGraph_map line 30
  5. theorem OAI.LeanBlast.SecondKahnKalai.edgeSupportGraph_noIsolates line 35
  6. def OAI.LeanBlast.SecondKahnKalai.supportIso line 43

    Source documentation

    Restriction of a graph isomorphism to its incident vertices.

    def supportIso {V W : Type*} {G : SimpleGraph V} {H : SimpleGraph W}
        (e : G ≃g H) : G.induce G.support ≃g H.induce H.support where
    …
  7. def OAI.LeanBlast.SecondKahnKalai.edgeSupportGraph_smulIso line 55
  8. theorem OAI.LeanBlast.SecondKahnKalai.map_eq_of_iso line 62
  9. theorem OAI.LeanBlast.SecondKahnKalai.exists_smul_eq_of_edgeSupportGraph_iso line 75

    Source documentation

    An isomorphism of incident-vertex graphs extends to a permutation of the full ambient vertex set, hence to equality of the corresponding edge copies.

    theorem exists_smul_eq_of_edgeSupportGraph_iso {S T : Finset (Edge n)}
        (e : edgeSupportGraph S ≃g edgeSupportGraph T) :
        ∃ σ : Equiv.Perm (Fin n), σ • S = T := by
    …

    Mentions: OAI.LeanBlast.SecondKahnKalai.Edge, OAI.LeanBlast.SecondKahnKalai.edgeSupportGraph

  10. theorem OAI.LeanBlast.SecondKahnKalai.subgraph_eq_edgeSubgraph line 95
  11. theorem OAI.LeanBlast.SecondKahnKalai.subgraph_eq_edgeSubgraph_of_iso line 113
  12. theorem OAI.LeanBlast.SecondKahnKalai.edgeCount_edgeSupportGraph line 124
  13. def OAI.LeanBlast.SecondKahnKalai.edgeSupportGraph_copy_of_subset line 134

    Source documentation

    A selected edge subset of an embedded graph pulls back to an actual copy inside the original graph, using only incident vertices of the selection.

    def edgeSupportGraph_copy_of_subset {V : Type*} (f : V ↪ Fin n)
        (H : SimpleGraph V) (S : Finset (Edge n))
        (hS : S ⊆ graphEdges (H.map f)) : (edgeSupportGraph S).Copy H := by
    …

    Mentions: OAI.LeanBlast.SecondKahnKalai.Edge, OAI.LeanBlast.SecondKahnKalai.graphEdges, OAI.LeanBlast.SecondKahnKalai.edgeSupportGraph

  14. theorem OAI.LeanBlast.SecondKahnKalai.exists_subgraph_iso_edgeSupportGraph line 156