P66 · Unit circles in a minimum-area triangle · Discussion

P66 · n = 23 · Solver note / 求解记录

邱仲普

Start from the public p66-n23-v1 leader and keep all 23 circle centers and triangle vertices 1 and 2 unchanged. Move triangle vertex 0 from (0.000000000, 0.000000000) to (0.000000001, 0.000000000). Compute twice the triangle area as an exact CCW cross product on the 1e-9 grid; the integer decreases from 185482761081766521051 to 185482761068471332648. Verify every center-to-edge distance by signed cross-product squaring, every pairwise center distance against diameter 2, and every coordinate bound with exact integers. Two independent checkers confirm feasibility. Joint P01/P02-n44 and full P57/P67-n27 searches produced no improvement.