import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int k = sc.nextInt();
        double ans = 0.0;
        for (int i = 1; i <= n; i++) {
            int sum = i;
            double tmp = 1.0 / (double)n;
            while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            }
            ans += tmp;
        }
        System.out.println(ans);
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int k = sc.nextInt();
        double ans = 0.0;
        for (int i = 1; i <= n; i++) {
            int sum = i;
            double tmp = 1.0 / (double)n;
            while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            }
            ans += tmp;
        }
        System.out.println(ans);
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int k = sc.nextInt();
        double ans = 0.0;
        for (int i = 1; i <= n; i++) {
            int sum = i;
            double tmp = 1.0 / (double)n;
            while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            }
            ans += tmp;
        }
        System.out.println(ans);
    } main {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int k = sc.nextInt();
        double ans = 0.0;
        for (int i = 1; i <= n; i++) {
            int sum = i;
            double tmp = 1.0 / (double)n;
            while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            }
            ans += tmp;
        }
        System.out.println(ans);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int k = sc.nextInt(); k sc.nextInt() sc.nextInt sc double ans = 0.0; ans 0.0 for (int i = 1; i <= n; i++) {
            int sum = i;
            double tmp = 1.0 / (double)n;
            while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            }
            ans += tmp;
        } int i = 1; int i = 1; i 1 i <= n i n i++ i++ i {
            int sum = i;
            double tmp = 1.0 / (double)n;
            while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            }
            ans += tmp;
        } {
            int sum = i;
            double tmp = 1.0 / (double)n;
            while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            }
            ans += tmp;
        } int sum = i; sum i double tmp = 1.0 / (double)n; tmp 1.0 / (double)n 1.0 (double)n while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            } sum < k sum k {
                sum *= 2;
                tmp /= 2.0;
            } sum *= 2 sum 2 tmp /= 2.0 tmp 2.0 ans += tmp ans tmp System.out.println(ans) System.out.println System.out System System.out ans String[] args args public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int k = sc.nextInt();
        double ans = 0.0;
        for (int i = 1; i <= n; i++) {
            int sum = i;
            double tmp = 1.0 / (double)n;
            while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            }
            ans += tmp;
        }
        System.out.println(ans);
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int k = sc.nextInt();
        double ans = 0.0;
        for (int i = 1; i <= n; i++) {
            int sum = i;
            double tmp = 1.0 / (double)n;
            while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            }
            ans += tmp;
        }
        System.out.println(ans);
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int k = sc.nextInt();
        double ans = 0.0;
        for (int i = 1; i <= n; i++) {
            int sum = i;
            double tmp = 1.0 / (double)n;
            while(sum < k) {
                sum *= 2;
                tmp /= 2.0;
            }
            ans += tmp;
        }
        System.out.println(ans);
    }
}