EXISTS_NOT_CONVConv.EXISTS_NOT_CONV : conv
Moves an existential quantification inwards through a negation.
When applied to a term of the form ?x.~P, the conversion
EXISTS_NOT_CONV returns the theorem:
|- (?x.~P) = ~(!x. P)
Fails if applied to a term not of the form ?x.~P.
Conv.FORALL_NOT_CONV,
Conv.NOT_EXISTS_CONV,
Conv.NOT_FORALL_CONV