#include <iostream>
#include <vector>
using namespace std;
bool checkEqualDifference(vector<int>& arr) {
int n = arr.size();
for (int i = 0; i < n - 2; ++i) {
for (int j = i + 1; j < n - 1; ++j) {
for (int k = j + 1; k < n; ++k) {
if (arr[i] - arr[j] == arr[j] - arr[k]) {
return true;
}
}
}
}
return false;
}
int main() {
int T;
cin >> T;
while (T--) {
int N;
cin >> N;
vector<int> arr(N);
for (int i = 0; i < N; ++i) {
cin >> arr[i];
}
if (checkEqualDifference(arr)) {
cout << "Yes" << endl;
} else {
cout << "No" << endl;
}
}
return 0;
}
