#include <bits/stdc++.h>
typedef long long ll;typedef unsigned long long ull; typedef double db;typedef long double ldb;
#define fre(x) freopen(#x ".in","r",stdin),freopen(#x ".out","w",stdout)
#define Rep(i,a,b) for(int i=a;i<=b;++i) 
#define Dwn(i,a,b) for(int i=a;i>=b;--i)
#define pii pair<int,int>
#define mair make_pair
#define fir first
#define sec second
#define int ll
using namespace std;

const int maxn=40+10,M=2e3+10,Mod=1e9+7,inv2=500000004;
const ull base=131;

int pw(int x,int p){int res=1,base=x;while(p){if(p&1)res=1LL*res*base%Mod;base=1LL*base*base%Mod;p>>=1;}return res;}
int Inv(int x){return pw(x,Mod-2);}
struct Sits{
	bitset<44>bit;
	int cnt[maxn];
	void Del(int x,int d){cnt[x]-=d;if(!cnt[x])bit[x]=0;}
	void Add(int x,int d){if(!cnt[x] && d)bit[x]=1;cnt[x]+=d;}
	ull Hash(){ ull hs=0; for(int i=1;i<=40;++i)hs=hs*base+cnt[i];return hs; }
}P[50000];
int tot=1;

int a[maxn],n;
struct eg{int from,to,next;int x,y;}e[M*M];
int head[40010],len;
void lqx(int from,int to,int x,int y)
{ e[++len].from=from,e[len].to=to,e[len].next=head[from],head[from]=len;e[len].x=x,e[len].y=y; }

unordered_map<ull,int>Vis;

void BDFS(){
	queue<int>q;
	P[1].bit.set(1);P[1].cnt[1]=n;
	q.push(1);Vis[P[1].Hash()]=1;
	while(!q.empty()){
		int u=q.front();q.pop();
		int x=P[u].bit._Find_first();
		Sits A=P[u];
		while(x<42 &&  P[u].bit[x]){
			if(P[u].cnt[x]>=2){
				A.Del(x,2);A.Add(x+x,1);
				if(Vis.find(A.Hash())==Vis.end()){ P[++tot]=A; q.push(tot);Vis[A.Hash()]=tot; }
				lqx(u,Vis[A.Hash()],x,x);
				A.Add(x,2),A.Del(x+x,1);
			}
			int y=P[u].bit._Find_next(x);
			while(y<42 && P[u].bit[y]){
				A.Del(x,1),A.Del(y,1),A.Add(x+y,1);
				if(Vis.find(A.Hash())==Vis.end()){ P[++tot]=A; q.push(tot);Vis[A.Hash()]=tot; }
				lqx(u,Vis[A.Hash()],x,y);
				A.Add(x,1),A.Add(y,1),A.Del(x+y,1);
				y=P[u].bit._Find_next(y);
			}
			x=P[u].bit._Find_next(x);
		}
	}
	cerr<<tot<<"\n";
	cerr<<len<<"\n";
}

int dp[41][40010];

int fac[M],inv[M];

void Init(const int N=1600){
	fac[0]=inv[0]=1;
	Rep(i,1,N)fac[i]=1LL*fac[i-1]*i%Mod;
	inv[N]=Inv(fac[N]);
	Dwn(i,N-1,1)inv[i]=1LL*(inv[i+1])*(i+1)%Mod;
}

int Down(int n,int m){if(n<m)return 0;return 1LL*fac[n]*inv[n-m]%Mod;}

void solve(){
	cin>>n;Rep(i,1,n-1)cin>>a[i];
	sort(a+1,a+n);BDFS();Init();
	dp[0][1]=1;
	Rep(x,1,n-1){
		if(x>1){
			for(int u=1;u<=tot;++u)if(dp[x-1][u]){
				int sum=0;
				int y=P[u].bit._Find_first();
				while(y<42 && P[u].bit[y]){
					sum+=(1LL*y*(y-1)/2*P[u].cnt[y])%Mod;
					y=P[u].bit._Find_next(y);
				}
				sum-=a[x-1];
				dp[x-1][u]=1LL*dp[x-1][u]*Down(sum,a[x]-a[x-1]-1)%Mod;
			}
		}
		for(int u=1;u<=tot;++u)if(dp[x-1][u]){
			for(int i=head[u];i;i=e[i].next){
				int v=e[i].to;int a=e[i].x,b=e[i].y;
				if(a!=b)dp[x][v]=(dp[x][v]+1LL*dp[x-1][u]*P[u].cnt[a]%Mod*a%Mod*P[u].cnt[b]%Mod*b%Mod)%Mod;
				else dp[x][v]=(dp[x][v]+1LL*dp[x-1][u]*P[u].cnt[a]%Mod*(P[u].cnt[a]-1)%Mod*inv2%Mod*a%Mod*a%Mod)%Mod;
			}
		}
	}
	int u;
	Rep(i,1,tot)if(P[i].bit[n]){u=i;break;}
	cerr<<dp[n-1][u]<<"\n";
	//dp[n-1][u]=1LL*dp[n-1][u]*pw(1LL*n*(n-1)/2,1LL*n*(n-1)/2-a[n-1])%Mod;
	int lim=n*(n-1)/2-a[n-1];
	Rep(i,1,lim)dp[n-1][u]=1LL*dp[n-1][u]*i%Mod;
	cout<<dp[n-1][u]<<"\n";
}

#undef int
int main (){ ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);return solve(),0; }