  The pseudo-Frobenius numbers of a numerical semigroup are those gaps of the
numerical semigroup that are maximal for the partial order induced by the
semigroup. We present a procedure to detect if a given set of integers is the
set of pseudo-Frobenius numbers of a numerical semigroup and, if so, to compute
the set of all numerical semigroups having this set as set of pseudo-Frobenius
numbers.
