#include <bits/stdc++.h>
using namespace std;
long long int mod = 1e18;
long long int mul(long long int a, long long int b) {
  return ((a % mod) * (b % mod)) % mod;
}
long long int add(long long int a, long long int b) {
  return ((a % mod) + (b % mod)) % mod;
}
long long int sub(long long int a, long long int b) {
  return ((a % mod) - (b % mod) + mod) % mod;
}
long long int gcdExtended(long long int a, long long int b, long long int *x,
                          long long int *y) {
  if (a == 0) {
    *x = 0, *y = 1;
    return b;
  }
  long long int x1, y1;
  long long int gcd = gcdExtended(b % a, a, &x1, &y1);
  *x = y1 - (b / a) * x1;
  *y = x1;
  return gcd;
}
long long int modInverse(long long int b) {
  long long int x, y;
  long long int g = gcdExtended(b, mod, &x, &y);
  if (g != 1) return -1;
  return (x % mod + mod) % mod;
}
long long int modDivide(long long int a, long long int b) {
  a = a % mod;
  long long int inv = modInverse(b);
  if (inv == -1)
    return -1;
  else
    return (inv * a) % mod;
}
long long int expFactor2(long long int n, long long int p) {
  long long int exponent = 0;
  while (n % p == 0) {
    exponent++;
    n /= p;
  }
  return exponent;
}
void sieve(long long int n, vector<bool> &prime, vector<long long int> &p) {
  prime[1] = 0;
  for (long long int i = 2; i <= n; i++) {
    if (prime[i]) {
      for (long long int j = i; j <= n; j += i) {
        if (j > i) prime[j] = 0;
        p[j] += expFactor2(j, i);
      }
    }
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long long int i, t, j, inp, n, a, b;
  cin >> t;
  vector<long long int> p(5000001, 0);
  vector<bool> prime(5000001, 1);
  sieve(5000001, prime, p);
  for (i = 2; i <= 5000000; i++) {
    p[i] += p[i - 1];
  }
  for (i = 0; i < t; i++) {
    cin >> a >> b;
    long long int ans = 0;
    ans = p[a] - p[b];
    cout << ans << '\n';
  }
  return 0;
}
