Environment v4.30.0. The archive's epoch is v4.33.0; only submissions in v4.30.0 can cite this work.
Proof of `Thatcher–Wright–Doner theorem for finite ranked trees` (1st statement)
What this proof establishes
no assumptions
Assuming the claims on the left, the claim on the right holds — checked by the archive's pipeline. Proof code is not displayed here.