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#pragma GCC optimize("O3")

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
//using namespace __gnu_pbds;

using ll = long long;
using ull = unsigned long long;
using ld = long double;
using str = string;
 
//typedef tree<ll, null_type, less_equal<ll>, rb_tree_tag, tree_order_statistics_node_update> oset;

void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
 
template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ", "; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? ", " : ""), __print(i); cerr << "}"; }
void _print() { cerr << "]\n"; }

template <typename T, typename... V>
void _print(T t, V... v) { __print(t); if (sizeof...(v)) cerr << ", "; _print(v...); }

#ifdef LOCAL
#define debug(x...) cerr << "\e[91m"<<__func__<<":"<<__LINE__<<" [" << #x << "] = ["; _print(x); cerr << "\e[39m" << endl;
#else
#define debug(x...)
#endif

const int mod = 1e9+7;
const ll infi  = 1e18+1;
const ld eps = 1e-14L;

int main(){
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int tt; cin >> tt;
    map<vector<int>, int> mp;
    while(tt--){
        int n; cin >> n;
        int graczy = 2*n;
        int kart = 4*n;
        vector<int> perm(kart);
        iota(perm.begin(), perm.end(), 1);
        int ans = 0;
        vector<int> a(graczy); for(auto &e : a) cin >> e;
        if(mp.find(a) != mp.end()){
            cout << mp[a] << '\n';
            continue;
        }
        set<vector<int>> bylo;
        int ita = 0;
        bool allowheura = true;
        int mn = 10, mx = -10;
        for(auto &e : a){
            mn = min(mn, e);
            mx = max(mx, e);
        }
        if(allowheura && mx - mn == 2){
            cout << 0 << '\n';
            continue;
        }
        bool gitt = true;
        for(int i=1;i<graczy;i++){
            if(i % 2){
                if(a[i] > a[i-1]) gitt = false;
            } else {
                if(a[i] < a[i-1]) gitt = false;
            }
        }
        if(allowheura && !gitt){
            cout << 0 << '\n';
            continue;
        }
        do {
            ita++;
            vector<int> b = perm;
            for(int i=1;i<kart;i+=2){
                if(b[i] < b[i-1]) swap(b[i], b[i-1]);
            }
            if(bylo.find(b) != bylo.end()) continue;
            bylo.insert(b);
            
            auto wynik = [&](auto&&self, int start, int it, int algomx, int algosec, int potmx, int potsec) -> int {
                if(it == graczy){
                    return (algomx > potmx) + (algosec > potsec); 
                }
                int pos = (start + it) % graczy;
                if(pos % 2){
                    return max(self(self, start, it+1, max(algomx, b[pos*2]), max(algosec, b[pos*2+1]), potmx, potsec),
                self(self, start, it+1, max(algomx, b[pos*2+1]), max(algosec, b[pos*2]), potmx, potsec));
                } else {
                    return min(self(self, start, it+1, algomx, algosec, max(potmx, b[pos*2]), max(potsec, b[pos*2+1])), 
                self(self, start, it+1, algomx, algosec, max(potmx, b[pos*2+1]), max(potsec, b[pos*2])));
                }
            };

            bool git = true;
            for(int i=0;i<graczy;i++){
                if(wynik(wynik, i, 0, 0, 0, 0, 0) != a[i]){
                   git = false;
                   break;
                }
            }
            ans += git;
            if(ans >= mod) ans -= mod;
        } while(next_permutation(perm.begin(), perm.end()));
        mp[a] = ans;
        cout << ans << '\n';
    }
    return 0;
}