#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<cstdlib>
#include<queue>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pr;
const double pi=acos(-1);
#define rep(i,a,n) for(int i=a;i<=n;i++)
#define per(i,n,a) for(int i=n;i>=a;i--)
#define Rep(i,u) for(int i=head[u];i;i=Next[i])
#define clr(a) memset(a,0,sizeof a)
#define pb push_back
#define mp make_pair
ld eps=1e-9;
ll pp=998244353;
ll mo(ll a,ll pp){if(a>=0 && a<pp)return a;a%=pp;if(a<0)a+=pp;return a;}
ll powmod(ll a,ll b,ll pp){ll ans=1;for(;b;b>>=1,a=mo(a*a,pp))if(b&1)ans=mo(ans*a,pp);return ans;}
ll read(){
    ll ans=0;
    char last=' ',ch=getchar();
    while(ch<'0' || ch>'9')last=ch,ch=getchar();
    while(ch>='0' && ch<='9')ans=ans*10+ch-'0',ch=getchar();
    if(last=='-')ans=-ans;
    return ans;
}
//head
#define N 1100
int n;
ll dp[N][N];
int a[N],m,s[N];
ll C[N][N];
void add(ll &a, ll b){
    a=(a+b)%pp;
}
void solved(){
    n=read();
    rep(i,1,n)a[i]=read();
    sort(a+1,a+n+1);
    int tot=0;
    m=0;
    rep(i,1,n){
        tot++;
        if(i==n || a[i]!=a[i+1]){
            s[++m]=tot;
            tot=0;
        }
    }
    rep(i,1,m)
        rep(j,0,n)dp[i][j]=0;
    dp[1][s[1]]=1;
    rep(i,1,m-1)
        rep(j,0,n)
            if(dp[i][j]){
                for(int k=0;k<=min(j,s[i+1]);k++)
                    add(dp[i+1][j-k+(s[i+1]-k)], dp[i][j]*C[j][k]%pp);
            }
    ll ans = 0;
    rep(j,0,n)add(ans,dp[m][j]);
    rep(i,1,m){
        rep(j,1,s[i])ans=ans*j%pp;
    }
    cout<<ans<<endl;
}
int main(){
    C[0][0]=1;
    rep(i,1,1000){
        C[i][0]=1;
        rep(j,1,i)
        C[i][j]=(C[i-1][j]+C[i-1][j-1])%pp;
    }
    int T=read();
    while(T--)solved();
    return 0;
}