using System;
using System.Collections.Generic;
using System.Linq;
using System.Numerics;

class Solution
{
    // nPk
    private static Dictionary<Tuple<int, int>, long> perms = new Dictionary<Tuple<int, int>, long>();
    public static long CalcPermutation(int n, int k)
    {
        var key = Tuple.Create(n, k);
        if (perms.ContainsKey(key))
        {
            return perms[key];
        }

        if (k == 0)
        {
            return 1;
        }
        var v = CalcPermutation(n - 1, k - 1) * n;
        perms[key] = v;
        return v;
    }

    // nCk
    private static Dictionary<Tuple<int, int>, long> combs = new Dictionary<Tuple<int, int>, long>();
    public static long CalcCombination(int n, int k)
    {
        var key = Tuple.Create(n, k);
        if (combs.ContainsKey(key))
        {
            return combs[key];
        }

        var v = CalcPermutation(n, k);
        for (int i = 2; i <= k; i++)
        {
            v /= i;
        }
        combs[key] = v;
        return v;
    }

    static BigInteger GetPattern(int n, int x)
    {
        if (n == 1)
        {
            return 1;
        }

        var pattern = (BigInteger)Math.Pow(n, x);
        for (int i = 1; i < n; i++)
        {
            pattern -= CalcCombination(n, i) * GetPattern(i, x);
        }
        return pattern;
    }

    static void Main()
    {
        var n = int.Parse(Console.ReadLine());

        if (n >= 130)
        {
            Console.WriteLine(1);
            return;
        }

        var allPattern = Math.Pow(6, n);
        var failPattern = GetPattern(6, n);
        var prov = (double)failPattern / allPattern;

        Console.WriteLine(prov);
    }
}