Is 'Hjsuidj***7348672' a wffl?

An atomic formula is a sequence of three symulus: A variable or constant, a relation, and a variable or constant.

A1: Ø = Ø       F1: ¬ (P)                        'A sequence of symbols' is not a wffl.
A2: Ø = E        F2: (P) ⇒ (Q)                ' ¬ (Ø = Ø) ' is a wffl. It is a sequence of
A3: E = Ø        F3: (P) ∨ (Q)                symulus composed using A1 and F1.
A4: X = Y        F4: (P) ∧ (Q)
A5: Ø ∈ Ø       F5: (P) ⇔ (Q)
A6: Ø ∈ R       F6: ∀X (P)
A7: S ∈ Ø       F7: ∃X (P)
A8: W ∈ A

Only a string of symulus built from atomic formula and rules F1 - F7 is a wffl.

Rules F1 - F7 are called compound formulae
             P and Q are the components of each compound formula

Rules F1 - F5 are called propositional forms.
            ONLY sequences of symbols built from F1 - F5 are propositional forms.
            P and Q are also propositional forms.

P and Q are propositional variables.
           The variable X is not a propositional variable.
                                X is an operator variable because it follows a quantifier.
If X did not follow a quantifier,
                        then X would be called an individual variable.

A logical formula is either a wffl or a propositional form. Finally, a proposition is a logical formula that has a truth value.