OP-00370 Open Permutation snarks without five-cycles CO · AIM Open Applied Problems · cycle permutation graphs · edge colourings · snarks
OP-00451 Open List edge-colouring with no extra colours CO · AIM Open Applied Problems · edge colourings · list colourings · multigraphs
OP-00563 Open The sharp degree bound for strong edge-colouring CO · AIM Open Applied Problems · Erdős–Nešetřil conjecture · strong chromatic index · strong edge-colourings
OP-00936 Open Rado's boundedness conjecture CO · colourings · linear equations · partition regularity · Rado's theorem