On the generalized Feng-Rao numbers of numerical semigroups generated by   intervals
  We give some general results concerning the computation of the generalized Feng-Rao numbers of numerical semigroups. In the case of a numerical semigroup generated by an interval, a formula for the $r^{th}$ Feng-Rao number is obtained. 
M. Delgado and J. I. Farr\'an and P. A. Garc\'ia-S\'anchez and D.   Llena
math.NT