#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cctype>
#include <cstring>

#include <iostream>
#include <sstream>
#include <string>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <algorithm>
using namespace std;

typedef pair<int, int> PII;
typedef long long ll;

#define FOR(i,a,b) for(int i = (a); i < (b); ++i)
#define FOR2(i,a,b) for(int i = (a); i > (b); --i)
//#define FOR(i,b) for(int i = 0; i < (b); ++i)
#define FORTO(i,a,b) for(int i = (a); i <= (b); ++i)
#define FORD(i,b) for(int i = (b)-1; i >= 0; --i)
#define FOREACH(it,a) for(typeof((a).begin()) it = (a).begin(); it != (a).end(); ++it)

#define $(x) int((x).size())

const int BASE = 10;

vector<int> to_big(int n)
{
	vector<int> res;
	while (n)
	{
		res.push_back(n%BASE);
		n /= BASE;
	}
	return res;
}

void print(const vector<int> & n)
{
	if (n.empty())
		printf("0\n");
	else
	{
		FOR2(i, n.size()-1, -1) printf("%d", n[i]);
		printf("\n");
	}
}

void add(vector<int> & a, const vector<int> & b) //a+=b
{
	int carry = 0;
	FOR(i, 0, b.size())
	{	
		if (a.size() == i) a.push_back(0);
		a[i] += b[i] + carry;
		carry = a[i] / BASE;
		a[i] %= BASE;
	}
	int ind = b.size();
	while (carry)
	{
		if (a.size() == ind) a.push_back(0);
		a[ind] += carry;
		carry = a[ind] / BASE;
		a[ind] %= BASE;
		++ind;
	}
}

void multiply_scalar(vector<int> & a, int b) //a *= b
{	
	int carry = 0;
	FOR(i, 0, a.size())
	{
		a[i] *= b;
		a[i] += carry;
		carry = a[i] / BASE;
		a[i] %= BASE;	
	}
	while (carry)
	{
		a.push_back(carry % BASE);
		carry /= BASE;
	}
}

vector<int> multiply(const vector<int> & a, const vector<int> & b) //c = a * b
{
	vector<int> res, zeros;
	FOR(i, 0, a.size())
	{
		if (a[i])
		{
			vector<int> temp = b;
			multiply_scalar(temp, a[i]);
			//cout << "temp: "; print(temp);
			temp.insert(temp.begin(), zeros.begin(), zeros.end());
			//print(temp);
			add(res, temp);
			//cout << "res: "; print(res);
		}
		zeros.push_back(0);
	}
	return res;
}

bool visited[107][107];
vector<int> dp[107][107];

vector<int> & go(int a, int b)
{
	if (visited[a][b])
		return dp[a][b];
	visited[a][b] = true;
	
	if (!a || !b) dp[a][b].push_back(1);
	else
	{
		add(dp[a][b], go(a-1, b));
		add(dp[a][b], go(a, b-1));
	}
	return dp[a][b];
}

struct Node
{
	Node(): left(NULL), right(NULL), nl(0), nr(0) { }
	Node * left, * right;
	int val;
	int nl, nr;
};

Node * insert(Node * n, int val)
{
	if (n == NULL)
	{
		n = new Node();
		n->val = val;
		return n;
	}
	if (val < n->val)
	{
		++(n->nl);
		n->left = insert(n->left, val);
	}
	else
	{
		++(n->nr);
		n->right = insert(n->right, val);
	}
	return n;
}

void del(Node * n)
{
	if (n->left) del(n->left);
	if (n->right) del(n->right);
	delete n;
}

vector<int> solve(Node * n)
{
	vector<int> res;
	if (!n)
		res.push_back(1);
	else
	{
		res = go(n->nl, n->nr);
		res = multiply(res, solve(n->left));
		res = multiply(res, solve(n->right));
	}
		
	return res;
}

void print(Node * n)
{
	printf("%d [%d] [%d]\n", n->val, n->nl, n->nr);
	if (n->left) print(n->left);
	if (n->right) print(n->right);
}

int main()
{	
	while (1)
	{
		int N;
		scanf("%d", &N);
		if (!N) break;	
		
		Node * root = NULL;
		FOR(i, 0, N)
		{
			int val;
			scanf("%d", &val);
			root = insert(root, val);
		}
		//print(root);
		
		vector<int> res = solve(root);
		
		print(res);
		del(root);
	}
	
	return 0;
}