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++) {

            double p = 1;
            int tmp = i;

            while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            }
            ans += p / n;
        }

        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++) {

            double p = 1;
            int tmp = i;

            while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            }
            ans += p / n;
        }

        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++) {

            double p = 1;
            int tmp = i;

            while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            }
            ans += p / n;
        }

        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++) {

            double p = 1;
            int tmp = i;

            while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            }
            ans += p / n;
        }

        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++) {

            double p = 1;
            int tmp = i;

            while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            }
            ans += p / n;
        } int i = 1; int i = 1; i 1 i <= n i n i++ i++ i {

            double p = 1;
            int tmp = i;

            while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            }
            ans += p / n;
        } {

            double p = 1;
            int tmp = i;

            while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            }
            ans += p / n;
        } double p = 1; p 1 int tmp = i; tmp i while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            } tmp < k tmp k {
                p *= 0.5;
                tmp *= 2;
            } p *= 0.5 p 0.5 tmp *= 2 tmp 2 ans += p / n ans p / n p n 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++) {

            double p = 1;
            int tmp = i;

            while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            }
            ans += p / n;
        }

        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++) {

            double p = 1;
            int tmp = i;

            while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            }
            ans += p / n;
        }

        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++) {

            double p = 1;
            int tmp = i;

            while (tmp < k) {
                p *= 0.5;
                tmp *= 2;
            }
            ans += p / n;
        }

        System.out.println(ans);
    }
}
