Lax Lean Archive

Triangles are outerplanar

Lax68.TriangleOuterplanar · concepts/Lax68/TriangleOuterplanar.lean · lax-68

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    Natural Language Statement

    Theorem

    Every triangle is outerplanar.

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

    Each proof establishes this claim relative to its assumptions.

    Lean source view on GitHub

    1import Lax68.Triangles
    2import Lax68.Outerplanar
    3
    4/-!
    5---
    6title: Triangles are outerplanar
    7type: theorem
    8---
    9Every triangle is outerplanar.
    10-/
    11
    12set_option autoImplicit false
    13
    14namespace Lax68.TriangleOuterplanar
    15
    16/-- Every triangle is outerplanar. -/
    17axiom triangle_outerplanar
    18 {V : Type*} {G : SimpleGraph V} :
    19 Lax68.Triangles.IsTriangle G →
    20 Lax68.Outerplanar.IsOuterplanar G
    21
    22end Lax68.TriangleOuterplanar
    23
    Show Proof
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