#include<bits/stdc++.h>
#define int long long
#define MOD 1000000007
using namespace std;
int n,a[5003],dp[53][3003],apr[503],jc[500003],njc[500003],nfp[500003],k1,k2,k3,k4,k5,k6,k7,k8,k9,ans;
int fstp(int X,int Y){
    int ret=1,bse=X;
    while(Y){
        if(Y%2)ret=ret*bse%MOD;
        bse=bse*bse%MOD;
        Y/=2;
    }
    return ret;
}
int C(int X,int Y){
    if(X<Y||X<0||Y<0)return 0;
    return (jc[X]*njc[Y]%MOD)*njc[X-Y]%MOD;
}
signed main(){
    ios::sync_with_stdio(false);
    nfp[0]=1;
    for(int i=1;i<=500000;i++)nfp[i]=nfp[i-1]*((MOD+1)/2)%MOD;
    jc[0]=1;
    for(int i=1;i<=500000;i++)jc[i]=jc[i-1]*i%MOD;
    njc[500000]=fstp(jc[500000],MOD-2);
    for(int i=499999;i>=0;i--)njc[i]=njc[i+1]*(i+1)%MOD;
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i];
        for(int j=0;j<a[i];j++)apr[j]++;
    }
    for(int i=n+1;i<=3000;i++)dp[0][i]=1;
    for(int i=1;i<=n;i++){
        for(int j=0;j<=i;j++){
            if(j%2==0)dp[0][i]=(dp[0][i]+(C(n,j)*fstp(i-j,n)%MOD)*njc[n])%MOD;
            else dp[0][i]=(dp[0][i]-(C(n,j)*fstp(i-j,n)%MOD)*njc[n])%MOD;
        }
    }
    for(int i=1;i<=50;i++){
        for(int j=1;j<=3000;j++){
            for(int u=0;u<=apr[i-1];u++){
                k1=nfp[apr[i-1]]*C(apr[i-1],u)%MOD;
                if(j*2-u<=3000&&j*2-u>=0)k1=k1*dp[i-1][j*2-u]%MOD;
                if(j*2-u<0)k1=0;
                dp[i][j]=(dp[i][j]+k1)%MOD;
            }
        }
    }
    ans=1;
    for(int i=1;i<=n;i++){
        k1=1;
        for(int j=50;j>=a[i];j--)k1=k1*nfp[apr[j]]%MOD;
        k1=k1*dp[a[i]][1]%MOD;
        ans=(ans-k1)%MOD;
    }
    ans%=MOD;
    ans+=MOD;
    ans%=MOD;
    cout<<ans<<'\n';
    return 0;
}