#include <fstream>
#include <algorithm>
#include <math.h>
#define ios ios_base::sync_with_stdio(false);
#define NMAX 1505
#define ERR 0.001


using namespace std;

int n,i,a,b,sol;

struct p{
    double x;
    double y;
}puncte[NMAX];

/*ifstream cin ("triang.in");
ofstream cout ("triang.out");*/

bool comp(p p1,p p2){
    if (p1.x==p2.x) return p1.y<p2.y;
    return p1.x<p2.x;
}

void citire(){
    cin>>n;
    for (i=1;i<=n;i++)
        cin>>puncte[i].x>>puncte[i].y;
    sort(puncte+1,puncte+n+1,comp);
}

double abs(double x){
if (x<0) return -x;
return x;}

int cbin(double x,double y){
    int st=1, dr=n, mij;
    while (st<=dr){
    mij=(st+dr)/2;
    if (abs(puncte[mij].x-x)<=ERR && abs(puncte[mij].y-y)<=ERR) return 1;
    if (puncte[mij].x<x) st=mij+1;
    else dr=mij-1;
    }
    return 0;
}

void rezolvare(){
    for (a=1;a<=n;a++)
    for (b=a+1;b<=n;b++){
        double x1,x2,y1,y2,ym,xm,m,dist;
        p p1,p2;
        p1.x=puncte[a].x;
        p1.y=puncte[a].y;
        p2.x=puncte[b].x;
        p2.y=puncte[b].y;
        xm=(p1.x+p2.x)/2;
        ym=(p1.y+p2.y)/2;
        //cout<<p1.x<<" "<<p1.y<<" "<<p2.x<<" "<<p2.y<<" "<<xm<<" "<<ym<<'\n';
        dist=(p1.x-p2.x)*(p1.x-p2.x)+(p1.y-p2.y)*(p1.y-p2.y);
        //cout<<dist<<'\n';
        dist*=3;
        //cout<<0.5d*sqrt(dist)<<" "<<p2.x-p1.x<<'\n';
        if (abs(p2.x-p1.x)<=ERR){
            y1=ym;
            y2=ym;
            x1=xm+0.5d*sqrt(dist);
            x2=xm-0.5d*sqrt(dist);
        }
        else
        {
        m=(p2.y-p1.y)/(p2.x-p1.x);
        //cout<<m<<'\n';
        x1=xm+0.5d*m*sqrt(dist/(m*m+1));
        y1=ym-0.5d*sqrt(dist/(m*m+1));
        x2=xm-0.5d*m*sqrt(dist/(m*m+1));
        y2=ym+0.5d*sqrt(dist/(m*m+1));
        }
        //cout<<x1<<" "<<y1<<" "<<x2<<" "<<y2<<'\n';
        sol+=cbin(x1,y1);
        sol+=cbin(x2,y2);
        //cout<<'\n';
    }
    cout<<sol/3;
}

int main()
{
    ios;
    cin.tie(0);
    cout.tie(0);
    citire();
    rezolvare();
    return 0;
}