© Monograph,
PUBLISHED by the AMS
Contents
Introduction
1.1 General concepts
1.2 A brief history of Coloring Theory
1.2.1 The Four-Color Problem
1.2.2 Perfect Graphs
1.2.3 Coloring the edges of a graph
1.2.4 Coloring of hypergraphs
1.3 Basic results on hypergraph coloring
1.3.1 Particular kinds of hypergraph coloring
1.3.2 A greedy hypergraph coloring algorithm
1.4 Hypertrees and chordal conformal hypergraphs
2.1 Basic definitions
2.2 Splitting-contraction algorithm
2.3 Basic properties of the upper chromatic number
2.4 Greedy C-hypergraph coloring algorithms
2.5 Algorithmic complexity
2.6 Open problems
3.1 Minimal uncolorable mixed hypergraphs
3.2 Uncolorability measures and a greedy algorithm
3.3 Colorability as an integer programming problem
3.4 Special types of uncolorable mixed hypergraphs
3.4.1 Complete (l,m)-uniform uncolorable mixed hypergraphs
3.4.2 A construction from subpaths of a graph
3.4.3 Colorability of mixed hypertrees
3.5 Open problems
4.1 Preliminary
4.2 Embeddings into uc
4.3 Separation on uc subhypergraphs
4.4 Recursive operations
4.4.1 Subset contraction
4.4.2 Orderings and unique colorability
4.5 Algorithmic complexity
4.6 UC mixed hypergraphs with χ ≥ n-2
4.7 Uniquely colorable mixed hypertrees
4.7.1Invertors, redundant C-edges and touching graphs
4.7.2 UC-ordering algorithm
4.8 Open problems
5.1 Basic concepts
5.2 Minimal non C-perfect mixed hypergraphs
5.3 C-perfection of mixed hypertrees
5.4 Algorithmic aspects of C-perfection
5.5 Open problems
6.1 The smallest mixed hypergraphs with gaps
6.2 Feasible sets and a doubling-shifting algorithm
6.3 Smaller realization
6.4 0-1 realization
6.5 Uniform bihypergraphs may have gaps
6.6 Separation on uc preserves continuity
6.7 Open problems
7.1 Colorings
7.2 Linear time algorithm for the upper chromatic number
7.3 Chromatic spectrum is continuous
7.4 Open problems
8.1 Preliminaries
8.2 Chromatic polynomial
8.3 Consequences and examples
8.4 A universal formula for chordal graphs
8.5 Open problems
9.1 Preliminaries
9.2 Unique colorability, n even
9.3 Unique colorability, n odd
9.4 Colorability and lower chromatic number
9.5 Upper chromatic number
9.6 Open problems
10.1 Classic planar hypergraphs
10.2 Coloring bitriangulations
10.3 Bounds for the upper chromatic number
10.4 Gap in the chromatic spectrum
10.5 Open problems
11.1 Steiner systems
11.2 Steiner triple systems
11.3 Steiner quadruple systems
11.4 Open problems
12.1 List colorings without lists
12.2 Ramsey, anti-Ramsey and related problems
12.3 Mixed hypergraphs and integer programming
12.4 Resource allocation
12.5 Lifetime of set systems
12.6 Parallel computing
12.7 Data Base Management
12.8 Molecular biology
12.9 Genetics of populations
12.10 Natural number interpretation