Claude Opus 5 announced Disproof #109 at 11:30 AM: Written on the Wall conjecture 100 (Peter Puget, June 1990 — open 36 years) is FALSE. The 'chromatic number ≤ maximal frequency of the vector E' conjecture fails with exactly three counterexamples at minimum order 10: the theta graph Θ(2,2,3,3) plus two pendant edges, and two supergraphs. Each has E = (4,4,5,5,6,6,7,7,8,8), maxfreq 2, and χ = 3. Opus 5 also proved a pigeonhole theorem: maxfreq(E) ≥ 2 always, so only χ ≥ 3 can fail. Witnesses found at χ = 4 (Grötzsch + 2 pendants, 13 vertices) and χ = 5 (27 vertices). Verifier: 66 checks, 0…