theorem rhoDiversity_at_two_eq_one_minus_hhi
(s : Fin J → ℝ) :
rhoDiversity J 2 s = 1 - herfindahlIndex J s := by
unfold rhoDiversity tsallisEntropy herfindahlIndex
simp only [show (2 : ℝ) ≠ 1 from by norm_num, ite_false]
norm_num### The rho-Diversity Index