RF vs float formulas: max relative discrepancy 1.80e-10
quartic negative tests (rejections out of 40): {'c4*3': 40, 'c4/3': 40, 'shift u by -0.1 (wrong range ok?)': 40, 't-range widened to t1/2': 40}
cells: lower c0 by 1.01*min(P-lines): rejected 60/60; raise c0 by 1.01*min h: rejected 60/60; double the a-width: rejected 27/60
exit 0 elapsed 2 s
