#include<bits/stdc++.h>

using namespace std;
typedef long long ll;

#define N 300010
const int mod = int (1e9 + 7);
int n;
int a[N], dp[N];
const int M = int(1e6 + 21);

map<int, vector<int>>ma;
vector<pair<int, int>>All, Last, Now;
vector<int>id[M], g[N];
void calc()
{
    sort(Last.begin(), Last.end());
    for (auto [l, r] : Last)
    {
        for (int L : ma[l - 1])
        {
            Now.push_back({L, r});
            All.push_back({L, r});
        }
        ma[r].push_back(l);
    }
    ma.clear();
}
int main()
{
    cin >> n;
    for (int i = 1; i <= n; i ++)cin >> a[i];
    for (int i = 1; i <= n; i ++)id[a[i]].push_back(i);
    for (int w = 1; w < M; w ++)
    {
        for (int x : id[w - 1])Last.push_back({x, x}), All.push_back({x, x});
        calc();
        Last = Now; Now.clear();
    }
    for (auto [l, r] : All)g[r].push_back(l - 1);
    dp[0] = 1;

    for (int i = 1; i <= n; i ++)
    {
        for (int j : g[i])dp[i] = (dp[i] + dp[j]) % mod;
    }
    
    cout << dp[n] << '\n';
    return 0;
}