Consider the following premises. There is at least one x_13 for which if x_13 were a sailor, then x_13 is climbing a mountain. For all x_13, x_13 will climb a mountain if and only if x_13 is a sailor. For all x_13, if x_13 climbs a mountain, then x_13 is a sailor. Can we infer the following from them? For all x_13, the fact that x_13 climbs a mountain does not imply that x_13 is a sailor.
That contradicts the premises. Therefore the answer is no.