#include <bits/stdc++.h>
using namespace std;
class TaskD {
 public:
  void solve(istream& in, ostream& out) {
    int n = 5000010;
    vector<bool> p(n + 1, 1);
    vector<int> cnt(n + 1, 0);
    vector<long long> cntall(n + 1, 0);
    p[0] = 0;
    p[1] = 0;
    for (int i = 2; i <= n; i++)
      if (p[i])
        for (int j = i; j <= n; j += i) {
          p[j] = 0;
          int num = j;
          while (!(num % i)) {
            num /= i;
            cnt[j]++;
          }
        }
    cntall[1] = cnt[1];
    for (int i = 2; i <= n; ++i) cntall[i] = cntall[i - 1] + cnt[i];
    int t;
    scanf("%d", &t);
    while (t--) {
      int a, b;
      scanf("%d %d", &a, &b);
      printf("%d\n", cntall[a] - cntall[b]);
    }
  }
};
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  TaskD solver;
  std::istream& in(std::cin);
  std::ostream& out(std::cout);
  solver.solve(in, out);
  return 0;
}
