#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint1000000007;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf 1000000001
 
 
int main(){
	
	int n;
	cin>>n;
	
	vector<int> p(n);
	rep(i,n)cin>>p[i];
	
	vector<mint> dp(2,0);
	dp[0] = 1;
	
	rep(i,n){
		vector<mint> ndp(2,0);
		rep(j,2){
			ndp[j] += dp[j];
			int nj = j;
			if(p[i]>50)nj ^= 1;
			ndp[nj] += dp[j];
		}
		swap(dp,ndp);
	}
	
	cout<<dp[1].val()<<endl;
	
	return 0;
}