// Task04.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <string>
#include <iostream>
using namespace std;

void primeFactors(int n);
bool isPrime3Factors(int n);

int _tmain(void)
{
	int count = 0;
	int a,b;
        cin >> a >> b;
	for (size_t i = a; i <= b; i++)
	{
		if (isPrime3Factors(i))
			count++;
		;
	}
	cout << count << endl;
	return 0;
}

bool isPrime3Factors(int n)
{
	int count = 0;
	while (n % 2 == 0)
	{
		if (++count > 3) return false;
		n = n / 2;
	}

	for (int i = 3; i <= sqrt(n); i = i + 2)
	{	
		while (n%i == 0)
		{
			if (++count > 3) return false;
			n = n / i;
		}
	}

	if (n > 2) ++count;
	return count == 3;
}