#pragma GCC target("avx2")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
#define DEBUG
#ifdef DEBUG
template <class T, class U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
    os << '(' << p.first << ',' << p.second << ')';
    return os;
}
template <class T> ostream &operator<<(ostream &os, const vector<T> &v) {
    os << '{';
    for(int i = 0; i < (int)v.size(); i++) {
        if(i) { os << ','; }
        os << v[i];
    }
    os << '}';
    return os;
}
void debugg() { cerr << endl; }
template <class T, class... Args>
void debugg(const T &x, const Args &... args) {
    cerr << " " << x;
    debugg(args...);
}
#define debug(...)                                                             \
    cerr << __LINE__ << " [" << #__VA_ARGS__ << "]: ", debugg(__VA_ARGS__)
#define dump(x) cerr << __LINE__ << " " << #x << " = " << (x) << endl
#else
#define debug(...) (void(0))
#define dump(x) (void(0))
#endif
using namespace std;
typedef long long ll;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<char> vc;
typedef vector<string> vs;
typedef vector<bool> vb;
typedef vector<double> vd;
typedef pair<ll,ll> P;
typedef pair<int,int> pii;
typedef vector<P> vpl;
typedef tuple<ll,ll,ll> tapu;
#define rep(i,n) for(int i=0; i<(n); i++)
#define REP(i,a,b) for(int i=(a); i<(b); i++)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
const int inf = (1<<30)-1;
const ll linf = 1LL<<61;
const int MAX = 510000;
int dy[8] = {0,1,0,-1,1,-1,-1,1};
int dx[8] = {-1,0,1,0,1,-1,1,-1};
const double pi = acos(-1);
const double eps = 1e-7;
template<typename T1,typename T2> inline bool chmin(T1 &a,T2 b){
	if(a>b){
		a = b; return true;
	}
	else return false;
}
template<typename T1,typename T2> inline bool chmax(T1 &a,T2 b){
	if(a<b){
		a = b; return true;
	}
	else return false;
}
template<typename T> inline void print(T &a){
    int sz = a.size();
    for(auto itr = a.begin(); itr != a.end(); itr++){
		cout << *itr;
        sz--;
        if(sz) cout << " ";
	}
    cout << "\n";
}
template<typename T1,typename T2> inline void print2(T1 a, T2 b){
	cout << a << " " << b << "\n";
}
template<typename T1,typename T2,typename T3> inline void print3(T1 a, T2 b, T3 c){
	cout << a << " " << b << " " << c << "\n";
}
void mark() {cout << "#" << "\n";}
ll pcount(ll x) {return __builtin_popcountll(x);}
const int mod = 1e9 + 7;
//const int mod = 998244353;

map<ll,ll> mp;
vl B(80,0);
vl v({2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71});
ll dp[2][1<<20];

int main(){
    ll a,b; cin >> a >> b;
    for(ll i=a; i<=b; i++){
        rep(j,20){
            if(i % v[j] == 0) B[i-a] |= 1<<j;
        }
    }
    dp[0][0] = 1;
    int bit = 1<<20;
    for(ll i=a; i<=b; i++){
        rep(j,bit) dp[1][j] = 0;
        rep(j,bit){
            dp[1][j] += dp[0][j];
            if((j & B[i-a]) == 0) dp[1][j+B[i-a]] += dp[0][j];
        }
        swap(dp[0],dp[1]);
    }
    ll ans = 0;
    rep(i,bit) ans += dp[0][i];
    cout << ans << "\n";
}
#include <bits/stdc++.h>
#define DEBUG if(0)
#define lli long long int
#define ldouble long double
using namespace std;

const int maxX = 72, maxPrimes = 20;
bool notPrime[maxX + 1];
vector<lli> primes;

const int maxN = 72;
lli a, b; int n;
int primesMask[maxN + 1];
lli memo[maxN + 1][1LL << maxPrimes];
lli solve(int i = 0, int mask = 0)
{
  if (i == n + 1)
    return 1;
  lli &ans = memo[i][mask];
  if (ans != -1)
    return ans;

  ans = solve(i + 1, mask);
  if (!(mask & primesMask[i]))
    ans += solve(i + 1, mask | primesMask[i]);
  return ans;
}

int main()
{
  notPrime[0] = notPrime[1] = true;
  for (int i = 2; i <= maxX; i ++)
  {
    if (!notPrime[i]) primes.push_back(i);
    for (int j = 0; i*primes[j] <= maxX; j ++)
    {
      notPrime[i*primes[j]] = true;
      if (i % primes[j] == 0) break;
    }
  }

  while (~scanf("%lld %lld", &a, &b))
  {
    n = b - a;
    for (lli i = a; i <= b; i++)
    {
      primesMask[i - a] = 0;
      for (int j = 0; j < primes.size(); j++)
      {
        int p = primes[j];
        if (i % p == 0)
          primesMask[i - a] |= (1LL << j);
      }
    }

    memset(memo, -1, sizeof(memo));
    lli ans = solve();
    printf("%lld\n", ans);
  }
  return 0;
}