#include <iostream>
#include <fstream>
using namespace std;
ifstream in("nrtri.in");
ofstream out("nrtri.out");
int n,v[801],u[801],c[30001];
int sol;
void citeste()
{
    in>>n;
    for(int i=1;i<=n;i++)
        in>>v[i];
}
void countSort()
{
    int i,k=0;
    for(i=1;i<=n;i++)
    {
        c[v[i]]++;
        if(v[i]>k)
            k=v[i];
    }
    for(i=1;i<=k;i++)
        c[i]+=c[i-1];
    for(i=1;i<=n;i++)
    {
        u[c[v[i]]]=v[i];
        c[v[i]]--;
    }
}
int bs(int st,int dr,int x)
{
    if(st>dr)
        return -1;
    int mij=st+(dr-st)/2;
    if(v[mij]>x)
        bs(st,mij-1,x);
    else
    {
        if(mij==dr)
            return mij;
        else if(v[mij+1]>x)
            return mij;
        else
            bs(mij+1,dr,x);
    }
}
int main()
{
    citeste();
    countSort();
    int i,j,x;
    for(i=1;i<=n-2;i++)
    {
        for(j=i+1;j<=n-1;j++)
        {
            x=bs(j+1,n,v[i]+v[j]); //cea mai mare pozitie pe care se afla un numar mai mic sau egal cu v[i]+v[j]
            if(x!=-1)
                sol+=x-j;
            for(int k=j+1;k<=x;k++)
                out<<v[i]<<" "<<v[j]<<" "<<v[k]<<"\n";
        }
    }
    out<<sol;
    return 0;
}