How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
Homogeneous vertex sets and the homogeneous number
Definition
Let be a finite graph. A vertex set is homogeneous if it is a clique or a stable set in (Cliques, stable sets, the clique number and stability number ). The homogeneous number of is
For the null graph, the published conventions give , and hence .
Depends on
Used by
- The Erdős–Hajnal property and an Erdős–Hajnal constant for a hereditary graph class Definition
- Every hereditary graph class of bounded order has the Erdős–Hajnal property Example
- For positive a,b, hom(K_a,b)=max{2,a,b} Example
- Kₙ and overline Kₙ both have homogeneous number n Example
- The classes of complete graphs and of empty graphs have Erdős–Hajnal constant 1 Example
- The self-complementary five-cycle satisfies hom(C₅)=2 Example
- Every nonempty n-vertex graph satisfies hom(G)≥ tfrac12 log₂ n Theorem
- Every P₃-free graph G satisfies hom(G)≥√|V(G)| Theorem
- For every n≥16 there is an n-vertex graph with hom(G)<3 log₂ n Theorem
- For every t≥1, the class of Kₜ-free graphs has the Erdős–Hajnal property Theorem
Dependency tree · next 3 levels
Direct dependencies and their dependencies through the next three levels: 30 results over 13 levels. An arrow runs from a result to what uses it, and this result sits at the bottom with a heavier outline. Click the chart to enlarge it.
Sources
- M. Chudnovsky, The Erdos-Hajnal Conjecture: A Survey, sec. 1 (standard reference, not scraped)
- A. Chernikov, MATH 223M notes, sec. 3.1 (standard reference, not scraped)