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The values of #BIS and #PP2DNF

Lax859101.BipartiteValues · concepts/Lax859101/BipartiteValues.lean · lax-859101

proven

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    Natural Language Statement

    Lemma

    The number counted by each of #BIS and #PP2DNF is invariant under isomorphism of instances, so the value of each problem on an instance is the number it counts.

    Concept map
    22 concepts
    100%
    Proven claimDefinitionThis conceptRelated conceptA → B: B builds on A
    Evidence

    This concept declares 4 statements. Each proof establishes one of them relative to its assumptions.

    1 sharpBIS_count_iso proven

    2 sharpBIS_eq proven

    3 sharpPP2DNF_count_iso proven

    4 sharpPP2DNF_eq proven

    Lean source view on GitHub

    1import Lax904597.Problems
    2import Lax904597.Sat
    3import Mathlib.ModelTheory.Graph
    4import Lax799700.SetFamily
    5import Lax366625.CountingProblems
    6import Lax366625.CountingClasses
    7import Lax366625.WitnessCounting
    8import Lax366625.CountingSat
    9import Lax859101.OneCallReductions
    10import Lax859101.SubtractiveReductions
    11import Lax859101.CountingDnf
    12import Lax859101.CountingNaeSat
    13import Lax859101.CountingRestrictedSat
    14import Lax859101.CountingAllSets
    15import Lax859101.CountingBipartite
    16
    17/-!
    18---
    19title: The values of #BIS and #PP2DNF
    20type: lemma
    21---
    22The number counted by each of #BIS and #PP2DNF is invariant under
    23isomorphism of instances, so the value of each problem on an instance is the
    24number it counts.
    25-/
    26
    27namespace Lax859101.BipartiteValues
    28
    29open FirstOrder FirstOrder.Language FirstOrder.Language.Structure
    30open Lax904597.Problems Lax904597.Sat Lax799700.SetFamily
    31open Lax366625.CountingProblems Lax366625.CountingClasses Lax366625.WitnessCounting
    32 Lax366625.CountingSat
    33open Lax859101.OneCallReductions Lax859101.SubtractiveReductions Lax859101.CountingDnf
    34 Lax859101.CountingNaeSat Lax859101.CountingRestrictedSat Lax859101.CountingAllSets
    35 Lax859101.CountingBipartite
    36
    37/-- The number counted by #BIS is isomorphism-invariant. -/
    38axiom sharpBIS_count_iso :
    39 ∀ {A B : Type} [Lax859101.CountingBipartite.bipGraph.Structure A]
    40 [Lax859101.CountingBipartite.bipGraph.Structure B],
    41 (A ≃[Lax859101.CountingBipartite.bipGraph] B) → Nat.card
    42 {S : A → Prop // BipIndep A S} = Nat.card {S : B → Prop // BipIndep B S}
    43
    44/-- The value of #BIS is the number it counts. -/
    45axiom sharpBIS_eq :
    46 ∀ (A : Type) [Lax859101.CountingBipartite.bipGraph.Structure A], SharpBIS A = Nat.card
    47 {S : A → Prop // BipIndep A S}
    48
    49/-- The number counted by #PP2DNF is isomorphism-invariant. -/
    50axiom sharpPP2DNF_count_iso :
    51 ∀ {A B : Type} [Lax859101.CountingBipartite.bipGraph.Structure A]
    52 [Lax859101.CountingBipartite.bipGraph.Structure B],
    53 (A ≃[Lax859101.CountingBipartite.bipGraph] B) → Nat.card
    54 {S : A → Prop // Pp2dnfModel A S} = Nat.card {S : B → Prop // Pp2dnfModel B S}
    55
    56/-- The value of #PP2DNF is the number it counts. -/
    57axiom sharpPP2DNF_eq :
    58 ∀ (A : Type) [Lax859101.CountingBipartite.bipGraph.Structure A], SharpPP2DNF A = Nat.card
    59 {S : A → Prop // Pp2dnfModel A S}
    60
    61end Lax859101.BipartiteValues
    62
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