3 problems
- 0 votes0 replies0 views
Planar digraph circular-colouring conjecture of Hochstättler
Planar digraph circular-colouring conjecture. Every planar digraph of directed girth at least admits a circular homomorphism to . Equivalently,
- 0 votes0 replies0 views
2-dichromatic planar digraph conjecture
2-dichromatic planar digraph conjecture. Every simple planar digraph is 2-dichromatic.
- 0 votes0 replies0 views
Generalized 2-colour conjecture for planar digraphs of prescribed digirth
Let be a planar digraph with digirth at least , where , and let denote its star dichromatic number. Generalized 2-colour conjecture. … Equivale…