theorem herfindahl_entry_decrease (J : ℕ) (hJ : 0 < J) :
equalWeightH (J + 1) < equalWeightH J := by
simp only [equalWeightH]
apply div_lt_div_of_pos_left one_pos
· exact_mod_cast hJ
· norm_cast
omegaHerfindahl Dynamics: Entry, Exit, and Merger Effects on Concentration