For every finite loopless undirected multigraph G with no bridges, there exists a multiset C of cycles in G such that every edge of G belongs to exactly two members of C, counted with multiplicity.
Assumptions
Finite undirected multigraph.
No loops and no bridges.
Parallel edges and repeated cycles in the cover are allowed.
Scope
Universal existence. The cited 2026 proof and formal endpoint are reported by their sources; independent mathematical assessment is pending.
Explanation
Proof outlines · 2
OpenAI proof account
Flow construction and cycle decomposition
The source proposes a full cycle double cover argument. The linked Lean project is a separate formal artifact for this account.
The project reports an unconditional proof endpoint using only standard logical axioms. It is linked as source evidence while mathematical assessment of the new proof remains pending.
Statement match: Linked by OpenMath · independent review separate · checked Oct 13, 2026