#include<stdio.h>

#include<algorithm>

using namespace std;

int main(){

freopen("nrtri.in","r",stdin);

freopen("nrtri.out","w",stdout);

int s1,s2,s3,j,n,i,c,v[1001];

c=0;

scanf("%d",&n);

for(i=1;i<=n;i++)

scanf("%d",&v[i]);

sort(v+1,v+n+1);

int pp=1;

for(i=1;i<n;i++){

if(pp==0){ i++; pp=1; }

s1=v[i]+v[i+1];

for(j=1;j<=n;j++){

s2=v[i]+v[j];

s3=v[i+1]+v[j];

if(i!=j&&j!=i+1){

if(s1>v[j]&&s3>v[i]&&s2>v[i+1]){

pp=0;

c++; }

}

}

}
printf("%d",c);
return 0;
}