#include <iostream>
#include <vector>

#include <atcoder/modint>

using Int = atcoder::modint998244353;

constexpr int K = 2;

#include <algorithm>
#include <numeric>

Int naive(int n, std::vector<int> p) {
    Int ans = 0;

    p.erase(p.begin());
    for (int& e : p) --e;

    std::vector<int> x(n);
    std::iota(x.begin(), x.end(), 0);
    do {
        bool ok = true;
        for (int i = 0, prev_min = 0; i < n; ++i) {
            ok &= p[i] < 0 or x[i] == p[i];
            if (i + K <= n) {
                int curr_min = *std::min_element(x.begin() + i, x.begin() + (i + K));
                ok &= prev_min <= curr_min;
                prev_min = curr_min;
            }
            if (not ok) break;
        }
        ans += Int{ ok };
    } while (std::next_permutation(x.begin(), x.end()));
    return ans;
}

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);

    int t;
    std::cin >> t;
    while (t--) {
        int n;
        std::cin >> n;
        std::vector<int> a(n + 1, -1);
        for (int i = 1; i <= n; ++i) {
            std::cin >> a[i];
        }

        assert(n <= 6);

        std::cout << naive(n, a).val() << std::endl;
    }
}