#include<stdio.h>
#include<algorithm>
using namespace std;
int v[801];
int main(){
    int n,i,j,k,cate=0;
    freopen("nrtri.in","r",stdin);
    freopen("nrtri.out","w",stdout);
    scanf("%d",&n);
    for(i=1;i<=n;i++)
        scanf("%d",&v[i]);
    sort(v+1,v+n+1);
    for(i=1;i<=n;i++)
        for(j=1;j<=n;j++)
            if(i!=j){
                k=j+1;
                while(k<=n){
                    if(k!=i&&k!=j)
                        if(v[i]+v[j]>=v[k]&&v[i]+v[k]>=v[j]&&v[k]+v[j]>=v[i])
                            cate++;
                    k++;
                }
            }
    printf("%d\n",cate/3);
    return 0;
    }