#include <bits/stdc++.h>
using namespace std;
const long long mod = 1e9 + 7;
const long double eps = 1e-9;
const long long INF = (1LL << 61);
const int inf = (1 << 30);
const int nn = 1e6 + 5;
vector<string> split(const string& s, char c) {
  vector<string> v;
  stringstream second(s);
  string x;
  while (getline(second, x, c)) v.emplace_back(x);
  return move(v);
}
void err(vector<string>::iterator it) {}
template <typename T, typename... Args>
void err(vector<string>::iterator it, T a, Args... args) {
  cerr << it->substr((*it)[0] == ' ', it->length()) << " = " << a << '\t';
  err(++it, args...);
}
bool chk(long long n) {
  for (long long i = 2; i * i <= n; i++) {
    if (n % i == 0) return false;
  }
  return true;
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  int t;
  cin >> t;
  while (t--) {
    long long a, b;
    cin >> a >> b;
    long long x = (a + b), y = abs(a - b);
    if (chk(x) && y == 1) {
      cout << "Yes"
           << "\n";
    } else
      cout << "No"
           << "\n";
  }
  return 0;
}
