#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf 1000000000000

struct Data{
	long long M=-Inf,m0 = Inf,m1 = Inf;
};

Data op(Data a,Data b){
	Data c;
	c.M = max(a.M,b.M);
	array<long long,4> A = {a.m0,a.m1,b.m0,b.m1};
	sort(A.begin(),A.end());
	c.m0 = A[0],c.m1 = A[1];
	return c;
	
}

Data e(){
	return Data();
}

int main(){
	
	int N;
	vector<long long> a;
	long long ans = 0LL;
	cin>>N;
	
	a.resize(N);
	vector<Data> D(N);
	rep(i,N){
		scanf("%lld",&a[i]);
		D[i] = Data();
		D[i].M = a[i];
		D[i].m0 = a[i];
	}
	
	segtree<Data,op,e> seg(D);
	
	rep(i,N-1){
		int ok = i+1,ng = N+1;
		while(ng-ok>1){
			int mid = (ok+ng)/2;
			auto ret = seg.prod(i,mid);
			if(ret.M <= ret.m0+ret.m1)ok = mid;
			else ng = mid;
		}
		ans += ok - (i+1);
	}
	
	cout<<ans<<endl;
	
	
	
    return 0;
}