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// #include <bits/stdc++.h>
#define FAST ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
#include <iostream>
#include <vector>
#include <map>
using namespace std;
#define MOD 1000000007

map<int, map<int, int64_t>> memo;
vector<int64_t> a;
int64_t wtf(int l, int r)
{
    if (l == r)
        return !((a[l] - a[l - 1]) % 2);

    int64_t tmp = memo[l][r];
    if (tmp)
    {
        if (tmp == -1)
        {
            return 0;
        }
        return tmp;
    }
    int64_t total = 0;
    if (!(((a[r] - a[l - 1]) % MOD) % 2))
    {
        total++;
    }
    for (int i = 0; i <= (r - l - 1); i++)
    {
        if (!(((a[l + i] - a[l - 1]) % MOD) % 2))
            total = (total + wtf(l + i + 1, r)) % MOD;
    }
    if (total == 0)
    {
        memo[l][r] = -1;
    }
    else
    {
        memo[l][r] = total;
    }
    return total;
}

int main()
{
    FAST int n;
    cin >> n;
    a.resize(n + 1);
    a[0] = 0;
    for (int i = 1; i <= n; i++)
    {
        cin >> a[i];
        a[i] += a[i - 1];
    }
    cout << wtf(1, n) << endl;
    return 0;
}