#include <cstdio>
#include <cstring>
#include <algorithm>
#define fo(i,a,b) for(int i=a;i<=b;i++)
#define fd(i,a,b) for(int i=a;i>=b;i--)
using namespace std;

typedef long long ll;

const int N=1e3+5,Mo=998244353;

int ty,n,a[N],C[N][N],f[N][2],g[N][2],fac[N];

int main() {
    fo(i,0,1e3) {
        C[i][0]=1;
        fo(j,1,i) C[i][j]=(C[i-1][j]+C[i-1][j-1])%Mo;
    }
    fac[0]=1;fo(i,1,1e3) fac[i]=(ll)fac[i-1]*i%Mo;
    for(scanf("%d",&ty);ty;ty--) {
        scanf("%d",&n);
        fo(i,1,n) scanf("%d",&a[i]);
        sort(a+1,a+n+1);int sum=0,ret=1;
        fo(i,0,n) f[i][0]=f[i][1]=0;
        for(int l=1,r=0;l<=n;l=r+1) {
            while (r<n&&a[r+1]==a[l]) r++;
            int x=r-l+1;
            if (l==1) f[0][1]=1;
            else {
                fo(i,0,sum+x-1) g[i][0]=g[i][1]=0;
                fo(j,0,sum-1) {
                    // 填开头
                    fo(i,1,min(sum-2*j,x)) (g[j+i][0]+=(ll)C[sum-2*j-1][i-1]*f[j][1]%Mo)%=Mo;
                    // 不填开头
                    fo(i,0,min(sum-2*j,x)) (g[j+i][0]+=(ll)C[sum-2*j][i]*f[j][0]%Mo)%=Mo;
                    fo(i,0,min(sum-2*j-1,x)) (g[j+i][1]+=(ll)C[sum-2*j-1][i]*f[j][1]%Mo)%=Mo;
                }
                fo(i,0,sum+x-1) f[i][0]=g[i][0],f[i][1]=g[i][1];
            }
            sum+=x;
            ret=(ll)ret*fac[x]%Mo;
        }
        int ans=0;
        fo(i,0,n-1) {
            (ans+=f[i][0])%=Mo;
            (ans+=f[i][1])%=Mo;
        }
        printf("%d\n",(ll)ans*ret%Mo);
    }
    return 0;
}