From the file attached I would like to know the following. if Y=n/ln(n), Is there a way of explicitly expressing n in terms of Y. Relations I found are: There are 2 values of n for every Y. Except at Y=e , the two values converge to n=e. If n1 and n2 are the values of n then n1^n2=n2^n1. So is there a way of finding n1, given n2? What could be the possible type of functions involved? From the graph it is seen that |n1-e| and |n2-e| are related inversely. What could be this relation?