#include <bits/stdc++.h>
using namespace std;
vector<int> sieve(int n) {
  vector<bool> prime(n + 1, true);
  prime[0] = false;
  prime[1] = false;
  int m = sqrt(n);
  vector<int> ans;
  for (int p = 2; p <= m; p++) {
    if (prime[p]) {
      for (int i = p * 2; i <= n; i += p) prime[i] = false;
    }
  }
  for (int i = 0; i < n; i++)
    if (prime[i]) ans.push_back(i);
  return ans;
}
int gcd(int a, int b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
int mod = 1e9 + 7;
int power(int a, long long b) {
  int res = 1;
  while (b) {
    if (b & 1) res = 1LL * res * a % mod;
    a = 1LL * a * a % mod;
    b >>= 1;
  }
  return res;
}
long long min(int a, long long b) {
  if (a > b) return b;
  return a;
}
long long max(int a, long long b) {
  if (a > b) return a;
  return b;
}
int v = INT_MAX, o = 0;
void solve() {
  vector<long long> arr(5000005, 0);
  for (int i = 1; i <= 5000000; i++) arr[i] = 0;
  for (int j = 4; j <= 5000000; j += 2) {
    long long k = j;
    while (k % 2 == 0) {
      arr[j]++;
      k /= 2;
    }
  }
  arr[2] = 1;
  for (int i = 3; i <= 5000000; i += 2) {
    if (arr[i] == 0) {
      for (int j = i; j <= 5000000; j += i) {
        long long k = j;
        while (k % i == 0) {
          arr[j]++;
          k /= i;
        }
      }
    }
  }
  arr[1] = 0;
  for (int i = 2; i <= 5000000; i++) {
    arr[i] += arr[i - 1];
  }
  int t;
  cin >> t;
  while (t--) {
    int a, b;
    cin >> a >> b;
    cout << arr[a] - arr[b] << "\n";
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int mul = 0;
  if (mul == 1) {
    int t;
    cin >> t;
    while (t--) {
      solve();
    }
  } else {
    solve();
  }
}
