#include <algorithm>
#include <iostream>
#include <cstdio>
#include <vector>
#include <set>
#include <map>
#include <queue>
using namespace std;

#define SIZE(s) int((s).size())
#define REP(i,n) for (int i=0; i<(n); i++)

class bigInt {
  public:
  vector<int> D;
  bigInt() { D.clear(); D.push_back(0); }
  bigInt(int x) { D.clear(); while (x) { D.push_back(x%10); x/=10; } }
};

bigInt comb[110][110];

class node {
  public:
    bigInt res;
    int size, val;
    node *left, *right, *up;
    node() { size=0; left=right=up=NULL; }
};

node *root;

void insert(int x) {
  if (root == NULL) {
    root = new node();
    root->val = x;
  } else {
    node *kde = root, *par = NULL;
    bool left;
    while (kde) {
      par = kde;
      if (x < kde->val) { kde=kde->left; left=true; } else { kde=kde->right; left=false; }
    }
    kde = new node();
    kde->up = par;
    if (left) par->left=kde; else par->right=kde;
    kde->val=x;
  }
}

void print(node *kde, int depth) {
  if (!kde) return;
  cout << string(2*depth,' ') << kde->val << endl;
  print(kde->left,depth+1);
  print(kde->right,depth+1);
}

bigInt utras(bigInt A) {
  int res=0;
  REP(i,SIZE(A.D)) {
    A.D[i] += res;
    res = A.D[i] / 10;
    A.D[i] %= 10;
  }
  while (res) { A.D.push_back(res%10); res/=10; }
  return A;
}

bigInt add(bigInt A, bigInt B) {
  bigInt res;
  res.D.resize( max( A.D.size(), B.D.size() ) );
  REP(i,SIZE(A.D)) res.D[i] += A.D[i];
  REP(i,SIZE(B.D)) res.D[i] += B.D[i];
  return utras(res);
}

bigInt mul(bigInt A, int x) {
  REP(i,SIZE(A.D)) A.D[i] *= x;
  return utras(A);
}

bigInt mul(bigInt A, bigInt B) {
  bigInt res(0);
  REP(i,SIZE(B.D)) {
    bigInt tmp = mul(A,B.D[i]);
    reverse( tmp.D.begin(), tmp.D.end() );
    REP(j,i) tmp.D.push_back(0);
    reverse( tmp.D.begin(), tmp.D.end() );
    res = add(res, tmp);
  }
  return res;
}

void print(const bigInt &B) {
  for (int i=SIZE(B.D)-1; i>=0; i--) printf("%d",B.D[i]);
  printf("\n");
}

void solve(node *kde) {
  if (!kde) return;
  solve(kde->left);
  solve(kde->right);
  kde->size = 1;
  int ls=0, rs=0;
  if (kde->left) ls = kde->left->size;
  if (kde->right) rs = kde->right->size;
  kde->size += ls+rs;

  kde->res = bigInt(1);
  bigInt L(1), R(1);
  if (kde->left) L = kde->left->res;
  if (kde->right) R = kde->right->res;
  kde->res = mul(kde->res,L);
  kde->res = mul(kde->res,R);
  kde->res = mul(kde->res,comb[ls+rs][ls]);
  // kde->res = mul(kde->res,bigInt(rs+1));
}

int main() {
  for (int n=0; n<=102; n++) for (int k=0; k<=n; k++) {
    if (k==0 || k==n) {
      comb[n][k] = bigInt(1);
    } else {
      comb[n][k] = add(comb[n-1][k-1], comb[n-1][k]);
    }
  }
  while (1) {
    int N;
    scanf("%d",&N);
    if (!N) break;
    root = NULL;
    for (int i=0; i<N; i++) {
      int x;
      scanf("%d",&x);
      insert(x);
    }
    solve(root);
    print(root->res);
  }
}