Problem dossier · Graph Decompositions

1-Factorization conjecture

Every d-regular graph on an even number n of vertices with d ≥ 2⌈n/4⌉ − 1 decomposes into perfect matchings (is 1-factorizable).

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Status

Proved for all sufficiently large n (Csaba–Kühn–Lo–Osthus–Treglown, 2016); small cases remain unconsolidated.

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The Angle of Attack

Test edge-coloring algorithms on small dense regular graphs at the threshold; search for the extremal graphs that make the bound tight.

Tags: matchings · edge coloring · regular graphs

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The Lab

No instruments built yet. When this problem gets tackled, its interactive instruments — explorers, searches, verifiers running in the browser — live here. See the Collatz dossier for what a fully tackled problem looks like.
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The Log

Empty. Work on this problem gets logged here as dated entries — constructions tried, code run, dead ends included. Dead ends are results.
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Related Problems

More open problems in Graph Decompositions and adjacent territory.