#include <bits/stdc++.h>
using namespace std;
bool ch(char c) {
  if (c >= 'a' && c <= 'z')
    return 1;
  else
    return 0;
}
bool ie(char a, char b) {
  bool f = 0;
  for (int i = a - 1; i <= a + 1; i++)
    for (int j = b - 1; j <= b + 1; j++)
      if (i != a && j != b && i == j && ch(i) && ch(j)) {
        f = 1;
        break;
      }
  if (f)
    return 1;
  else
    return 0;
}
int main() {
  int t;
  cin >> t;
  while (t--) {
    int n;
    cin >> n;
    string s;
    cin >> s;
    int p = n / 2 - 1, q = p + 1;
    bool f = 1;
    while (p >= 0) {
      if (ie(s[p], s[q]) == 0) {
        f = 0;
        break;
      }
      p--;
      q++;
    }
    if (f)
      cout << "YES\n";
    else
      cout << "NO\n";
  }
  return 0;
}
