2026-08-31, price_the_band.py, lanes A and B
Estimate written before launching. Two solves were timed first, on this machine: X=40, J=200 took 5.7 s and X=80, J=320 took 40.1 s. That is an exponent of 2.81 in X, so the remaining rungs price at roughly 123 s (X=120), 276 s (X=160) and 866 s (X=240).
- Lane A, one pass over five rungs: about 22 minutes. Two passes, out-of-band on and the in-band control, about 44 minutes.
- Lane B, seven solves at the fixed
X=80, J=320grid: about 5 minutes. - Total estimate: about 49 minutes, on the operator's laptop. Peak memory at the largest rung is a constraint matrix near 200 MB, which is why the ladder stops at
X=240; anything larger goes to GitHub Actions.
Every solve checkpoints to artifacts/ as it completes, so an interruption keeps what it has already paid for.
An earlier claim in conversation that this sweep would take two days was wrong, and was made before anything was timed. Recorded because the repo's compute rule exists to stop exactly that.
outcome: lane B measured separately after the first sweep was killed (91% of the gain sits inside alpha in (1, 1.5]); the out-of-band information is worth about +0.0068 at the measure level (class value 0.6793, method error 2.2e-3), and no autocorrelation-kernel certificate can reach it; lane A stopped at X=160 when the X=240 rung exceeded an hour and the sweep was killed there, which is why lane B was run on its own afterwards
2026-08-31, the X=240 out-of-band rung, re-run to completion
No new estimate was written; the rung was restarted and left alone, which is the thing the rule above exists to stop. It finished at 10598 s, twelve times the 866 s estimate. The wall times 5.8, 40.4, 428.4, 2069.1, 10597.9 s at X = 40, 80, 120, 160, 240 scale as X^2.8 only across the first pair; the later steps run at X^4 to X^5.5, so the first-pair estimate was the wrong instrument for the rungs that mattered. Value 0.6828907, checkpointed into artifacts/lane-a-convergence.json. Anything past this goes to CI.
2026-09-01, refit.py
Seconds of compute. Re-extrapolates both ladders three ways from the checkpointed artifacts.
outcome: the earlier class value 0.6793 was one fit among several; the difference route gives 0.6790, the direct out-of-band fit 0.6815, and pinning the exponent moves the difference limit across 0.0027 to 0.0071. RESULTS.md §1 now states the range [0.679, 0.682] and withdraws the coincidence with CGdL's 0.6792