# Edge coloring

## Packing T-joins ★★

Author(s): DeVos

**Conjecture**There exists a fixed constant (probably suffices) so that every graft with minimum -cut size at least contains a -join packing of size at least .

## Acyclic edge-colouring ★★

Author(s): Fiamcik

**Conjecture**Every simple graph with maximum degree has a proper -edge-colouring so that every cycle contains edges of at least three distinct colours.

Keywords: edge-coloring

## A generalization of Vizing's Theorem? ★★

Author(s): Rosenfeld

**Conjecture**Let be a simple -uniform hypergraph, and assume that every set of points is contained in at most edges. Then there exists an -edge-coloring so that any two edges which share vertices have distinct colors.

Keywords: edge-coloring; hypergraph; Vizing

## List colorings of edge-critical graphs ★★

Author(s): Mohar

**Conjecture**Suppose that is a -edge-critical graph. Suppose that for each edge of , there is a list of colors. Then is -edge-colorable unless all lists are equal to each other.

Keywords: edge-coloring; list coloring

## Universal Steiner triple systems ★★

Author(s): Grannell; Griggs; Knor; Skoviera

**Problem**Which Steiner triple systems are universal?

Keywords: cubic graph; Steiner triple system

## Edge list coloring conjecture ★★★

Author(s):

**Conjecture**Let be a loopless multigraph. Then the edge chromatic number of equals the list edge chromatic number of .

Keywords:

## Seymour's r-graph conjecture ★★★

Author(s): Seymour

An -*graph* is an -regular graph with the property that for every with odd size.

**Conjecture**for every -graph .

Keywords: edge-coloring; r-graph

## Goldberg's conjecture ★★★

Author(s): Goldberg

The *overfull parameter* is defined as follows:

**Conjecture**Every graph satisfies .

Keywords: edge-coloring; multigraph

## Strong edge colouring conjecture ★★

A strong edge-colouring of a graph is a edge-colouring in which every colour class is an induced matching; that is, any two vertices belonging to distinct edges with the same colour are not adjacent. The strong chromatic index is the minimum number of colours in a strong edge-colouring of .

**Conjecture**

Keywords: