#include <math.h>
#include <stdio.h>
#include <stdlib.h>

typedef long long ll;

/* Calculates gcd(a,b): the greatest common divisor of a and b */
static ll gcd(ll a, ll b)
{
    while (b)
    {
        ll tmp = a%b;
        a = b;
        b = tmp;
    }
    return a;
}

static ll *memo;

/* Calculates number of ordered pairs (a,b) such that gcd(a,b) == 1 */
static ll calc2(ll a, ll lim)
{
    ll *m, b;

    m = &memo[a];
    if (*m == 0)
    {
        for (b = 0; b < lim; ++b)
        {
            if (gcd(a, b) == 1) ++*m;
        }
    }
    return *m;
}

/* Calculates number of ordered triples (a,b,c) such that gcd(a,b,c) == 1 */
static ll calc(ll lim)
{
    ll res = 0, a, b;

    memo = calloc(lim, sizeof(ll));
    memo[0] = 1;
    memo[1] = lim;
    for (a = 0; a < lim; ++a)
    {
        res += calc2(a, lim);
        for (b = 0; b < a; ++b)
        {
            res += 2*calc2(gcd(a, b), lim);
        }
    }
    free(memo);
    return res;
}

ll main()
{
    ll depth;
    for (depth = 1; depth <= 16; ++depth)
    {
        ll lim = 1 << depth;
        ll cnt = calc(lim);
        ll tot = lim*lim*lim;
        printf("%2lld:  %15lld / %15lld = %.9f\n", depth, cnt, tot, (double)cnt/tot);
    }
    return 0;
}