#line 1 "cp_templates/template/template.hpp"
# include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
const double pi = acos(-1);
template<class T>constexpr T inf() { return ::std::numeric_limits<T>::max(); }
template<class T>constexpr T hinf() { return inf<T>() / 2; }
template <typename T_char>T_char TL(T_char cX) { return tolower(cX); }
template <typename T_char>T_char TU(T_char cX) { return toupper(cX); }
template<class T> bool chmin(T& a,T b) { if(a > b){a = b; return true;} return false; }
template<class T> bool chmax(T& a,T b) { if(a < b){a = b; return true;} return false; }
int popcnt(unsigned long long n) { int cnt = 0; for (int i = 0; i < 64; i++)if ((n >> i) & 1)cnt++; return cnt; }
int d_sum(ll n) { int ret = 0; while (n > 0) { ret += n % 10; n /= 10; }return ret; }
int d_cnt(ll n) { int ret = 0; while (n > 0) { ret++; n /= 10; }return ret; }
ll gcd(ll a, ll b) { if (b == 0)return a; return gcd(b, a%b); };
ll lcm(ll a, ll b) { ll g = gcd(a, b); return a / g*b; };
ll MOD(ll x, ll m){return (x%m+m)%m; }
ll FLOOR(ll x, ll m) {ll r = (x%m+m)%m; return (x-r)/m; }
template<class T> using dijk = priority_queue<T, vector<T>, greater<T>>;
# define all(qpqpq)           (qpqpq).begin(),(qpqpq).end()
# define UNIQUE(wpwpw)        (wpwpw).erase(unique(all((wpwpw))),(wpwpw).end())
# define LOWER(epepe)         transform(all((epepe)),(epepe).begin(),TL<char>)
# define UPPER(rprpr)         transform(all((rprpr)),(rprpr).begin(),TU<char>)
# define rep(i,upupu)         for(ll i = 0, i##_len = (upupu);(i) < (i##_len);(i)++)
# define reps(i,opopo)        for(ll i = 1, i##_len = (opopo);(i) <= (i##_len);(i)++)
# define len(x)                ((ll)(x).size())
# define bit(n)               (1LL << (n))
# define pb push_back
# define exists(c, e)         ((c).find(e) != (c).end())

struct INIT{
	INIT(){
		std::ios::sync_with_stdio(false);
		std::cin.tie(0);
		cout << fixed << setprecision(20);
	}
}INIT;

namespace mmrz {
	void solve();
}

int main(){
	mmrz::solve();
}
#line 1 "cp_templates/data_structure/segment_tree.hpp"

template<typename T>struct segment_tree {
	using F = function<T(T, T)>;

	int offset;
	int n;
	vector<T> node;
	F combine;
	T identify;

	segment_tree(vector<T> v, F _combine, T _identify) : combine(_combine), identify(_identify) {
		n = (int)v.size();
		offset = 1;
		while(offset < n)offset <<= 1;

		node.resize(2*offset, identify);

		for(int i = 0;i < n;i++)node[i + offset] = v[i];
		for(int i = offset - 1;i >= 1;i--)node[i] = combine(node[2 * i + 0], node[2 * i + 1]);
	}

	segment_tree(int _n, F _combine, T _identify) : n(_n), combine(_combine), identify(_identify){
		
		offset = 1;
		while(offset < _n)offset <<= 1;
		node.assign(2*offset, identify);
	}

	T operator[](int x) {return node[x + offset]; }

	void set(int x, T val){
		x += offset;

		node[x] = val;
		while(x >>= 1){;
			node[x] = combine(node[2 * x + 0], node[2 * x + 1]);
		}
	}

	T fold(int a, int b){
		T L = identify, R = identify;
		for(a += offset, b += offset; a < b;a >>= 1, b >>= 1){
			if(a&1)L = combine(L, node[a++]);
			if(b&1)R = combine(node[--b], R);
		}
		return combine(L, R);
	}

	int max_right(const function<bool(T)> f, int l = 0){
		if(l == n)return n;
		l += offset;
		T sum = identify;
		do{
			while(l%2 == 0)l >>= 1;
			if(not f(combine(sum, node[l]))){
				while(l < offset){
					l <<= 1;
					if(f(combine(sum, node[l]))){
						sum = combine(sum, node[l]);
						++l;
					}
				}
				return l - offset;
			}
			sum = combine(sum, node[l]);
			++l;
		}while((l&-l) != l);
		return n;
	}

	int min_left(const function<bool(T)> f, int r = -1){
		if(r == 0)return 0;
		if(r == -1)r = n;
		r += offset;
		T sum = identify;
		do{
			--r;
			while(r > 1 && (r % 2))r >>= 1;
			if(not f(combine(node[r], sum))){
				while(r < offset){
					r = r*2 + 1;
					if(f(combine(node[r], sum))){
						sum = combine(node[r], sum);
						--r;
					}
				}
				return r+1 - offset;
			}
			sum = combine(node[r], sum);
		}while((r&-r) != r);
		return 0;
	}
};
#line 3 "1435.cpp"

using namespace mmrz;

struct s{
	int m1, m2, mx;
	s(int _m1, int _m2, int _mx) : m1(_m1), m2(_m2), mx(_mx) {}
};

void SOLVE(){
	int n;
	cin >> n;
	segment_tree<s> seg(n, [](s l, s r) -> s {
		int m1 = min(l.m1, r.m1);
		int m2 = min({max(l.m1, r.m1), l.m2, r.m2});
		int mx = max(l.mx, r.mx);
		return s{m1, m2, mx};
	}, s{hinf<int>(), hinf<int>(), -1});

	rep(i, n){
		int a;
		cin >> a;
		seg.set(i, s{a, hinf<int>(), a});
	}

	ll ans = 0;
	auto check = [&](const s x) -> bool {
		return (x.m1 + x.m2 >= x.mx);
	};

	rep(l, n){
		int r = seg.max_right(check, l);
		ans += max<int>(0, r-l-1);
	}

	rep(r, n){
		int l = seg.max_right(check, r+1);
		ans += max<int>(0, (r + 1) - l - 1);
	}

	cout << ans << endl;

}

void mmrz::solve(){
	int t = 1;
	//cin >> t;
	while(t--)SOLVE();
}