AI-found graph refutes a Koch–Narayan domination bound

A bipartite graph on 13 vertices has 22 edges and a unique minimum dominating set of size 4, exceeding the proposed bound m(13,4)=21 in Koch–Narayan Conjecture 1.

Sources for this record

What was already known

Koch and Narayan proved restricted cases and conjectured the broader edge bound for bipartite graphs with a unique minimum dominating set.

AI involvement AI-centered

Claude agents found the counterexample in John Erlbacher’s directed Demonstrandum campaign. Erlbacher audited its verification gates.

Claude agents supplied the witness under Erlbacher’s direction; individual-result autonomy is not documented.

Importance Modest

Corrects a specific proposed bound in domination theory.

Limitations

The assessment covers this 13-vertex witness. Separate claims about global minimum size or uniqueness up to isomorphism are not included; the source checks both readings of a printed formula typo.

Technical verification Formal (exact computation)

Two clean-room exact checkers reportedly enumerate the graph and its dominating sets, including both readings of a formula typo.

Independent checking

exact computation

Checker
cleanroom_check.py and independently written indy_check.py
Scope
The 13-vertex γ=4, s=22 witness against Conjecture 1
Basis
Reported by the linked checker
Evidence source

Human understanding Few

No named person explains the individual construction; Few is the evidence default.

Correction and publication history