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[00G] (Solved on 2022-10-11) Well-formed formulas are
a formula of the type \( Β¬ (πΌ)\) where \(πΌ\) is a well-formed formula, or
a formula of the type \( (πΌ) β (π½) \) , or
a formula of the type \( (πΌ) β (π½) \) , or
a formula of the type \( (πΌ) β¨ (π½) \) , or
a formula of the type \( (πΌ) β§ (π½) \) ,
where \(πΌ,π½\) are two well-formed formulas.