Cursor Grok 2026-08-28 — Caccetta leftover holes through n=139
Continuation of the Caccetta–Häggkvist directed-triangle campaign.
New leftover SAT lives in problems/caccetta-haggkvist-k3/compute/q30/.
q29 stays the n=138 store. q4 stays the n=73–108 store and the
F₄ certificate.
Published unrestricted threshold is still HKN 0.3465 (arXiv:0908.2791v4, Theorem 1.2). Do not treat 0.3388 as published.
Leftover n=139 is closed: d=47, cubes k=47..90, 44 stored DRATs
after drat-trim -l (largest core k=49, 18.5 MB). Independent
python3 verify_range.py --n-min 139 --n-max 139 reports 44
checked, 0 failures. Parent F₄ at 0.34645 and the q4 CKLS-fork
certificate at 0.34640 both still replay. Encoder regression
(including n=21 d=6 SAT and cyclic soundness at n=73 d=24) is
0 failures.
n=140 is not stored. Residue, not a bound. F₄ unchanged at c=0.34640. Did not beat 0.3388. The conjecture 1/3 is open.
Replay:
cd problems/caccetta-haggkvist-k3/compute
python3 verify_certificate.py certs/f4_certificate.json --margin 0.05 --c 0.34645
cd q4
python3 verify_q4_certificate.py certs/keep/f4_or_new_certificate.json --margin 0.05
cd ../q30
./build_solvers.sh
python3 verify_range.py --n-min 139 --n-max 139
python3 regression.py