The $\textit{well-formed formulas (wff)}$ of propositional logic are obtained by using the following rules:
1. An atomic proposition $\phi$ is a well-formed formula.
2. If $\phi$ is a well-formed formula, then so is $\neg \phi.$
3. If $\phi$ and $\psi$ are well-formed formulas, then so are $(\phi \vee \psi), (\phi \wedge \psi), (\phi \rightarrow \psi),$ and $(\phi \leftrightarrow \psi).$
4. If $\phi$ is a well-formed formula, then so is $(\phi).$
Now, consider the following statements:
$1.\neg (\neg P \wedge \neg \neg R)$
$2.\neg(P,Q,\wedge R)$
$3.(\neg P)(\neg Q)\wedge (\neg P)$
$4.(P\vee Q)(P\vee R)$
$5. (P) \vee (\neg P)$
$6. P \rightarrow (\neg Q)$
$7. (\neg \neg \neg \neg P)$
(P, Q and R are atomic propositions)
Total number of well-formed formulas are ______