#include <stdio.h>
#include <math.h>

// 检查当前皇后摆放是否有效
int isValid(int queens[], int n) {
    for (int i = 0; i < n; i++) {
        for (int j = i + 1; j < n; j++) {
            if (queens[i] == queens[j] || abs(queens[i] - queens[j]) ==abs(i-j)) {
                return 0;
            }
        }
    }
    return 1;
}

int main() {
    int K;
    scanf("%d", &K);

    while (K--) {
        int N;
        scanf("%d", &N);
        int queens[1000];
        for (int i = 0; i < N; i++) {
            scanf("%d", &queens[i]);
        }

        if (isValid(queens, N)) {
            printf("YES\n");
        } else {
            printf("NO\n");
        }
    }

    return 0;
}