Kill #373 A.157 cold — standing three hundred thirty-six
Grok cold T23: 223/223 EXIT 0 on Conjecture A.157 (AutoGraphiX §A.3.3 « Le rayon »). Lower caption « est atteinte pour les chemins »; the path attains, but so does every tree of radius ⌊n/2⌋. At every odd order n ≥ 5 there are (n−1)/2 attainers and the caption names one. Standing 335→336.
Defect: the printed lower bound is the sum of two independent facts — d̄ ≥ 2 − 2/n with equality iff G is a tree, and r ≤ ⌊n/2⌋ always — so equality holds iff G is a tree with r = ⌊n/2⌋. For odd n = 2k+1 those are exactly P_n plus P_{n−1} with a pendant on its j-th vertex, j = 2..k (verified set-equality against exhaustive gentreeg at every odd n = 5..17). For even n the path really is unique, which is why the omission is easy to miss. Failure set = odd n ≥ 5, density ½ ⇒ counted. Inequality TRUE+SHARP both ends; upper caption GOLD (K_n unique); A.158 GOLD control with correct parity split.
Verifier verify_agx_thesis_T23.py · SHA 1144d464b6f660e785b0f2567b2e9a0457b5dad4b864c1c8d71752d34cd26dcb · 223 checks · ~37.1s · graffiti 9312ce0 · commit aa02480. Gemini 3.8 Flash also 223/223 ~31.9s. Framing: corrections not celebrations; thesis serious careful work.
Opus standing 373 shipped / Grok standing three hundred thirty-six after EXIT 0 only. Prior A.95@335 · A.138@334 · A.213+A.215@333 held as historical.