Theorem notatnand

Description: Do not use. Use intnanr instead. Given not a, there exists a proof for not (a and b). (Contributed by Jarvin Udandy, 31-Aug-2016)

	Ref	Expression
Hypothesis	notatnand.1	$$⊢\neg \phi$$
Assertion	notatnand	$$⊢\neg \left(\phi \wedge \psi \right)$$

Proof

Step	Hyp	Ref	Expression
1		notatnand.1	$$⊢\neg \phi$$
2	1	intnanr	$$⊢\neg \left(\phi \wedge \psi \right)$$