Item 3.3.5.d.

Negation: There is a natural number \(n\) which is prime but not solitary.

Converse: For all natural numbers \(n\text{,}\) if \(n\) is solitary, then \(n\) is prime.

Contrapositive: For all natural numbers \(n\text{,}\) if \(n\) is not solitary then \(n\) is not prime.