It is also proved that the number of gaps of the numerical semigroup generated by integers p and q with g.c.d.(p, q) = 1, in the interval [pq − (k + 1)(p + q), . . . , pq − k(p + q)] is equals to2(k + 1) +
It is also proved that the number of gaps of the numerical semigroup generated by integers p and qwith g.c.d.(p, q) = 1, in the interval [pq − (k + 1)(p + q), . . . , pq − k(p + q)] is equals to2(k + 1) +kqp+kpqfor each k = 1, . . . ,pqp + q− 1.