Claude reports the general four-color Rado formula

For four colors, with x=y allowed, the reported proof gives R(c)=40c+41 for every integer c≥2 in x+y+c=z. It reduces the universal statement to R(2)=121 and two unsatisfiable spoke templates.

Sources for this record

What was already known

Myers conjectured the formula, and earlier work bounded R(c) between 40c+41 and 44c+45. A previous Claude result covered c+1 divisible by 3, 4, 5 or 7 and some individual values.

AI involvement AI-led

The submitter credits Claude Fable 5 with the new spoke relaxation, proof, Lean reduction and SAT computations under human operational direction. A complete interaction transcript is unavailable.

The source credits Claude with the central new spoke construction and proof; autonomy beyond the stated operational direction is not independently documented.

Importance Notable

Claims the remaining general case of a specialist four-color Rado conjecture.

Limitations

c=0 and c=1 are exceptions. The repository reports Lean reduction and DRAT checks, but the large DRAT proof files are hash-pinned rather than shipped, and no human mathematician has reviewed the bridge from templates to the intended statement.

Technical verification Formal (Lean 4; exact SAT/DRAT certificate checking)

The repository reports DRAT-checked unsatisfiability of both finite templates, exact base-case checks, and a Lean 4 conditional reduction with a template hash bridge. This is a reported machine check of the full claim chain, not rerun here; human proof review is absent.

Formal checking

Lean proof and regenerated-template hash check

Checker
Lean 4 kernel via Rado.lean and verify.sh
Scope
Conditional universal reduction from two template UNSAT facts and R(2)=121 to R(c)=40c+41 for all c>=2
Basis
Reported by the linked checker
Evidence source

Formal checking

Exact SAT solves and DRAT verification; separate encoder and finite-case checks

Checker
kissat and drat-trim, with independent encoder and solver cross-checks
Scope
UNSAT of M(3,1,1) and M(3,2,2) and required finite base values
Basis
Reported by the linked checker
Evidence source

Checking a formal statement does not establish that it matches the original problem.

Human understanding Few

Default for missing human explanation: the supplied proof describes the spoke mechanism, but the repository explicitly reports no human mathematical review or explanation.

Correction and publication history