#include <bits/stdc++.h>

using namespace std;

ifstream fin("nrtri.in");
ofstream fout("nrtri.out");

const int MAXN = 801;

int v[801];
int main()
{
    int n, i, j, k, cnt, aux;

    fin >> n;

    for (i = 0; i < n; i++)
        fin >> v[i];

    cnt = 0;

    for (i = 0; i < n - 2; i++)
        for (j = i + 1; j < n - 1; j++)
            for (k = j + 1; k < n; k++) {
                aux = max(v[i], v[j]);

                if (v[i] == max(aux, v[k])) {
                    if(v[j] + v[k] >= v[i])
                        cnt++;
                }

                else if (v[j] == max (aux, v[k])) {
                    if (v[i] + v[k] >= v[j])
                        cnt++;
                }
                else {
                    if(v[j] + v[i] >= v[k])
                        cnt++;
                }
            }
    fout << cnt;
    return 0;
}