Draft — mutable and not usable as a dependency; its citation marks the draft state.

Lax5.MonadicDependence

Monadic dependence

concepts/Lax5/MonadicDependence.lean · Lax5

nothing to prove

Definition

A graph class is monadically dependent (also called monadically NIP) if it does not transduce the class of all graphs.

Lean source view on GitHub

1import Lax5.GraphClasses
2import Lax5.GraphTransductions
3
4/-!
5---
6title: Monadic dependence
7type: definition
8---
9A graph class is monadically dependent (also called monadically NIP) if
10it does not transduce the class of all graphs.
11
12# Formalization notes
13
14This is the standard transduction-based definition from the model theory
15of graph classes, stated over the transduction relation of the
16prerequisite concepts.
17-/
18
19namespace Lax5.MonadicDependence
20
21open Lax5.GraphClasses
22
23/-- A graph class is monadically dependent if it does not transduce the
24class of all finite simple graphs. -/
25def MonadicallyDependent (C : GraphClass) : Prop :=
26 ¬ GraphTransductions.Transduces C allGraphs
27
28end Lax5.MonadicDependence
29

Formalization notes

This is the standard transduction-based definition from the model theory of graph classes, stated over the transduction relation of the prerequisite concepts.

Mathlib imports

none