#include <bits/stdc++.h>
using namespace std;
// #define LOCAL // 提出時はコメントアウト
#define DEBUG_

typedef long long ll;
const double EPS = 1e-9;
const ll INF = ((1LL<<62)-(1LL<<31));
typedef vector<ll> vecl;
typedef pair<ll, ll> pairl;
template<typename T> using uset = unordered_set<T>;
template<typename T, typename U> using mapv = map<T,vector<U>>;
template<typename T, typename U> using umap = unordered_map<T,U>;

#define ALL(v) v.begin(), v.end()
#define REP(i, x, n) for(int i = x; i < n; i++)
#define rep(i, n) REP(i, 0, n)
#define sz(x) (ll)x.size()
ll llceil(ll a,ll b) { return (a+b-1)/b; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> vector<vector<T>> genarr(ll n, ll m, T init) { return vector<vector<T>>(n,vector<T>(m,init)); }

///// DEBUG
#define DUMPOUT cerr
#define repi(itr, ds) for (auto itr = ds.begin(); itr != ds.end(); itr++)
template<typename T>istream&operator>>(istream&is,vector<T>&vec){for(T&x:vec)is>>x;return is;}
template<typename T,typename U>ostream&operator<<(ostream&os,pair<T,U>&pair_var){os<<"("<<pair_var.first<<", "<<pair_var.second<<")";return os;}
template<typename T>ostream&operator<<(ostream&os,const vector<T>&vec){os<<"{";for(int i=0;i<vec.size();i++){os<<vec[i]<<(i+1==vec.size()?"":", ");}
os<<"}";return os;}
template<typename T,typename U>ostream&operator<<(ostream&os,map<T,U>&map_var){os<<"{";repi(itr,map_var){os<<*itr;itr++;if(itr!=map_var.end())os<<", ";itr--;}
os<<"}";return os;}
template<typename T>ostream&operator<<(ostream&os,set<T>&set_var){os<<"{";repi(itr,set_var){os<<*itr;itr++;if(itr!=set_var.end())os<<", ";itr--;}
os<<"}";return os;}
void dump_func(){DUMPOUT<<endl;}
template<class Head,class...Tail>void dump_func(Head&&head,Tail&&...tail){DUMPOUT<<head;if(sizeof...(Tail)>0){DUMPOUT<<", ";}
dump_func(std::move(tail)...);}
#ifndef LOCAL
#undef DEBUG_
#endif
#ifdef DEBUG_
#define DEB
#define dump(...)                                                          \
DUMPOUT << "  " << string(#__VA_ARGS__) << ": "                            \
        << "[" << to_string(__LINE__) << ":" << __FUNCTION__ << "]"        \
        << endl                                                            \
        << "    ",                                                         \
    dump_func(__VA_ARGS__)
#else
#define DEB if (false)
#define dump(...)
#endif

//////////

#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")


int solve(ostringstream &cout) {
    #ifdef LOCAL
    ifstream in("../../Atcoder/input.txt");
    cin.rdbuf(in.rdbuf());
    #endif

    ll A,B;
    cin>>A>>B;

    ll N = B - A + 1;
    vecl P = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71};
    while (sz(P) > 0 && N < P.back()) P.pop_back();

    ll U = 1LL<<sz(P);
    auto dp = genarr(N+1,U+1,0LL);

    dp[0][0] = 1;
    ll ans = 0;
    rep(i,N) {
        ll x = i + A;
        ll mask = 0;
        rep(j,sz(P)) {
            if (x % P[j]) continue;
            mask += 1LL<<j;
        }
        rep(S,U) {
            if ((mask & S) == 0) dp[i+1][S | mask] += dp[i][S];
            dp[i+1][S] += dp[i][S];
        }
        if (i == N-1) {
            rep(S,U) ans += dp[i+1][S];
        }
    }

    cout << ans << endl;

    return 0;
}

int main() {
    ostringstream oss;
    int res = solve(oss);

    cout << oss.str();
    return res;
}

#include <stdio.h>

using namespace std;

long long pr[20] = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71};
long long a, b, n, ans = 1;
long long dp[1 << 21];
long long te[73];

void dfs(long long now, long long t) {
  if (t == n) {
    return;
  }
  for (int i = t; i < n; i++) {
    if (!(now & te[i])) {
      dfs(now | te[i], i + 1);
      ans++;
    }
  }
}

int main() {
  long long a, b;
  scanf("%lld%lld", &a, &b);
  n = b - a + 1;
  for (long long i = a; i <= b; i++) {
    for (int j = 0; j < 20; j++) {
      if (i % pr[j] == 0) {
        te[i - a] = te[i - a] | (1 << j);
      }
    }
  }
  dfs(0, 0);
  printf("%lld", ans);
}