The first author showed that the list chromatic number of every graph with average degree d is at least (0.5-o(1))log2d. We prove that for r<3, every r-uniform hypergraph in which at least half of the (r-1)-vertex subsets are contained in at least d edges has list chromatic number at least lnd100r3. When r is fixed, this is sharp up to a constant factor.
All Science Journal Classification (ASJC) codes
- Theoretical Computer Science
- Discrete Mathematics and Combinatorics
- List coloring