have IH := notAnd (p₂::ps) hnAndTail
l : List Prop
p₁ p₂ : Prop
ps : List Prop
h : ¬andN (p₁ :: p₂ :: ps)
hnAndTail : ¬andN (p₂ :: ps)
⊢ ¬p₁ ∨ orN ((¬p₂) :: map Not ps)
l : List Prop
p₁ p₂ : Prop
ps : List Prop
h : ¬andN (p₁ :: p₂ :: ps)
hnAndTail : ¬andN (p₂ :: ps)
IH : orN (notList (p₂ :: ps))
⊢ ¬p₁ ∨ orN ((¬p₂) :: map Not ps)