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NOT_EXISTS_CONV                                                 (Conv)
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NOT_EXISTS_CONV : conv

SYNOPSIS
Moves negation inwards through an existential quantification.

KEYWORDS
conversion, quantifier, existential, negation.

DESCRIBE
When applied to a term of the form {~(?x.P)}, the conversion
{NOT_EXISTS_CONV} returns the theorem:

   |- ~(?x.P) = !x.~P




FAILURE
Fails if applied to a term not of the form {~(?x.P)}.

SEEALSO
Conv.EXISTS_NOT_CONV, Conv.FORALL_NOT_CONV, Conv.NOT_FORALL_CONV.

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