import java.io.*;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.PriorityQueue;

class Pair
{
    public long value;
    public long count;

    public Pair(long value,long count)
    {
        this.value = value;
        this.count = count;
    }
}

public class Main
{
    private static int MOD = 1000000007;

    private static long prefixNCR[];

    private static void preComputePrefixNCR(int size)
    {
        prefixNCR = new long[size+1];

        prefixNCR[0] = 1;
        prefixNCR[2] = 1;
        prefixNCR[4] = 3;

        for(int i = 6;i <= size;i += 2)
        {
            prefixNCR[i] = ((i-1) * prefixNCR[i-2])%MOD;
        }
    }

    private static long countPairings(long skillSet[],int persons)
    {
        HashMap<Long,Long> map = new HashMap<>();

        for(int i = 0;i < persons;i++)
        {
            if(map.containsKey(skillSet[i]))
            {
                map.put(skillSet[i],map.get(skillSet[i])+1);
            }
            else
            {
                map.put(skillSet[i],(long)1);
            }
        }

        PriorityQueue<Pair> pq = new PriorityQueue<>((Pair p1,Pair p2) -> {

            if(p1.value < p2.value)
            {
                return 1;
            }
            else
            {
                return -1;
            }
        });

        for(Map.Entry<Long,Long> entry : map.entrySet())
        {
            long value = entry.getKey();
            long count = entry.getValue();

            pq.add(new Pair(value,count));
        }

        long count = 1;

        while(!pq.isEmpty())
        {
            Pair max = pq.poll();

            if (max.count % 2 == 0)
            {
                count = (count * prefixNCR[(int)max.count]) % MOD;
            }
            else
            {
                count = (count * (max.count * prefixNCR[(int)(max.count - 1)]) % MOD) % MOD;

                Pair secondMax = pq.poll();

                if (secondMax.count % 2 != 0)
                {
                    count = (count * (secondMax.count * prefixNCR[(int)(secondMax.count - 1)])%MOD) % MOD;
                }
                else
                {
                    count = (count * secondMax.count) % MOD;

                    secondMax.count -= 1;

                    pq.add(secondMax);
                }
            }
        }

        return count;
    }

    public static void main(String[] args) throws IOException
    {
        BufferedReader br =  new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        StringBuilder outputString = new StringBuilder();

        preComputePrefixNCR(100000);

        int testCases = Integer.parseInt(br.readLine());

        while(testCases --> 0)
        {
            int persons = Integer.parseInt(br.readLine());

            long skillSet[] = Arrays.stream(br.readLine().split(" ")).mapToLong(c->Long.parseLong(c)).toArray();

            outputString.append(countPairings(skillSet,persons)).append("\n");
        }

        bw.write(outputString.toString());
        bw.close();
    }
}