tauto
case neg.h1
v u x : VarName
phi : Formula
phi_ih : ∀ (binders : Finset VarName), ¬isFreeIn v phi → admitsAux v u binders phi
binders : Finset VarName
h1 : ¬(¬v = x ∧ isFreeIn v phi)
c1 : ¬v = x
⊢ ¬isFreeIn v phi
no goals