Approximate formulation of the probability that the Determinant or   Permanent of a matrix undergoes the least change under perturbation of a   single element
  In an earlier paper, we discussed the probability that the determinant of a matrix undergoes the least change upon perturbation of one of its elements, provided that most or all of the elements of the matrix are chosen at random and that the randomly chosen elements have a fixed probability of being non-zero. In this paper, we derive approximate formulas for that probability by assuming that the terms in the permanent of a matrix are independent of one another, and we apply that assumption to several classes of matrices. In the course of deriving those formulas, we identified several integer sequences that are not listed on Sloane's Web site. 
Genta Ito