#include <stdio.h>
#define NM 801

using namespace std;

FILE *f=fopen("nrtri.in","r");
FILE *g=fopen("nrtri.out","w");

int i,N,c,t[NM],s[4];

void v()
{
    bool ok(0);
    if(t[s[1]]+t[s[2]]<t[s[3]]) ok=1;
    if(t[s[2]]+t[s[3]]<t[s[1]]) ok=1;
    if(t[s[3]]+t[s[1]]<t[s[2]]) ok=1;
    if(!ok) c++;
}

void b(int k)
{
    for(int i=1;i<=N;i++)
     if(i>s[k-1])
     {
        s[k]=i;
        if(k==3) v();
        else b(k+1);
     }

}

int main()
{
    fscanf(f,"%d",&N);
    for(i=1;i<=N;i++)
     fscanf(f,"%d",&t[i]);
    b(1); fprintf(g,"%d",c);
    return 0;
}