import java.util.Scanner;

public class Main {

    static Scanner stdIn = new Scanner(System.in);
    public static void main(String[] args) {
        int n = stdIn.nextInt();
        int k = stdIn.nextInt();

        double kakuritu;
        
        int length;
        if(n<k){
            length = n;
            kakuritu = 0.0;
        }else{
            length = k;
            kakuritu = ((double)1/n)*(n-k);
        }

        for(int i=1; i<=length; i++){
            double tempkakuritu = 1;
            tempkakuritu *= (double)1/n;

            int tempi= i;
            for(; tempi<k; tempi*=2){
                tempkakuritu *= 0.5;
            }

            kakuritu += tempkakuritu;
        }

        System.out.println(kakuritu);

    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz