The Fermat axis is the central line connecting the first and second Fermat points. It has line function l = a(b^2 - c^2)(a^2 - b^2 - b c - c^2)(a^2 - b^2 + b c - c^2), corresponding to Kimberling center X_526. It passes through Kimberling centers X_i for i = 6 (symmedian point), 13 (first Fermat point), 14 (second Fermat point), 113, 115 (center of the Kiepert hyperbola), 265, 381, 399, 542, 1625, 1879, 1989, 2341, 2437, 2465, 2466, 3013, 3014, 3015, 3016, 3017, 3018, and 3019.

central line | Fermat points | first Fermat point | second Fermat point

Pierre de Fermat