#include <bits/stdc++.h>
#pragma GCC target("avx2")
#pragma GCC optimization("O3")
#pragma GCC optimization("unroll-loops")
using namespace std;
const int fx[] = {+1, -1, +0, +0};
const int fy[] = {+0, +0, +1, -1};
void err(istream_iterator<string> it) {}
template <typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args) {
  cerr << *it << " = " << a << endl;
  err(++it, args...);
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long t;
  cin >> t;
  while (t--) {
    long long n;
    cin >> n;
    long long a[n];
    for (long long i = 0; i < n; i++) {
      cin >> a[i];
    }
    sort(a, a + n);
    bool flag = true;
    while (count(a, a + n, 0) != (n - 1)) {
      long long cnt = 0;
      for (long long i = 0; i < n; i++) {
        if (a[i] == 0) continue;
        for (long long j = 0; j < n; j++) {
          if (i == j) continue;
          if (a[j] == 0) {
            continue;
          }
          if (abs(a[i] - a[j]) <= 1) {
            if (a[i] <= a[j]) {
              a[i] = 0;
            } else {
              a[j] = 0;
            }
            cnt++;
            break;
          }
        }
      }
      if (cnt == 0) {
        flag = false;
        break;
      }
    }
    if (flag) {
      cout << "YES" << endl;
    } else {
      cout << "NO" << endl;
    }
  }
  return 0;
}
