#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;
}