Answer
$\exists$ integers a, b, and c such that a − b is even and b − c is
even and a − c is not even.
Work Step by Step
Recall the form of the negation of a universal conditional statement:
$~(\forall x, P(x) \rightarrow Q(x)) \equiv \exists x$ such that $(P(x) \land $ ~$Q(x))$
