#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <set>
#include <stack>
#include <tuple>
#include <deque>
#include <array>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <chrono>
#include <random>
#include <limits>
#include <iterator>
#include <functional>
#include <sstream>
#include <fstream>
#include <complex>
#include <cstring>
#include <unordered_map>
#include <unordered_set>
using namespace std;

using ll = long long;
constexpr int INF = 1001001001;
// constexpr int mod = 1000000007;
constexpr int mod = 998244353;

template<class T>
inline bool chmax(T& x, T y){
    if(x < y){
        x = y;
        return true;
    }
    return false;
}
template<class T>
inline bool chmin(T& x, T y){
    if(x > y){
        x = y;
        return true;
    }
    return false;
}

template<typename T>
struct BinaryIndexedTree{
    vector<T> data;
    int sz;

    BinaryIndexedTree(int n){
        sz = n + 2;
        data.assign(sz, 0);
    }

    void add(int i, T x){
        ++i;
        while(i < sz){
            data[i] += x;
            i += i & -i;
        }
    }

    // [0, i] の区間和
    T sum(int i){
        T res = 0;
        ++i;
        while(i > 0){
            res += data[i];
            i -= i & -i;
        }
        return res;
    }

    // [l, r) の区間和
    T sum(int l, int r){
        if(l > r)   return 0;
        return sum(r - 1) - sum(l - 1);
    }

    // val 以上を満たす 0-indexed の位置を返す
    int lower_bound(T val){
        // if(val <= 0)    return -1;
        int res = 0;
        int n = 1;
        while(n < sz)   n <<= 1;
        for(int k = n >> 1; k > 0; k >>= 1){
            if(res + k < sz && data[res + k] < val){
                val -= data[res + k];
                res += k;
            }
        }
        return res;     // 1-indexed であれば、res + 1 を返す
    }
};

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int N;
    cin >> N;
    vector<int> a(N), compress;
    for(int i = 0; i < N; ++i){
        cin >> a[i];
        compress.emplace_back(a[i]);
    }
    sort(begin(compress), end(compress));
    compress.erase(unique(begin(compress), end(compress)), end(compress));
    int C = compress.size();
    
    BinaryIndexedTree<int> bit(C);
    ll ans = 1;
    bit.add(lower_bound(begin(compress), end(compress), a[0]) - begin(compress), 1);
    bit.add(lower_bound(begin(compress), end(compress), a[1]) - begin(compress), 1);
    int l = 0;
    for(int r = 2; r < N; ++r){
        bit.add(lower_bound(begin(compress), end(compress), a[r]) - begin(compress), 1);
        int m1 = compress[bit.lower_bound(1)];
        int m2 = compress[bit.lower_bound(2)];
        int M = compress[bit.lower_bound(bit.sum(0, C))];
        while(M > m1 + m2 && l + 1 < r){
            bit.add(lower_bound(begin(compress), end(compress), a[l++]) - begin(compress), -1);
            m1 = compress[bit.lower_bound(1)];
            m2 = compress[bit.lower_bound(2)];
            M = compress[bit.lower_bound(bit.sum(0, C))];
        }
        ans += r - l;
    }

    cout << ans << endl;

    return 0;
}