#include <iostream>
#include <fstream>
#include <cmath>
#include <algorithm>
using namespace std;
ifstream fin("triang.in");
ofstream fout("triang.out");
#define eps 0.001
struct point{double x, y;
friend bool operator < (const point &a, const point &b){
return a.x < b.x || (a.x == b.x && a.y < b.y);
}
};
double len(point a, point b){
return sqrt((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y));
}
bool checkeq(double d1, double d2){
return (d1-d2 < eps && d2-d1 < eps);
}
bool checkpoint(point a, point b){
return checkeq(a.x, b.x) && checkeq(a.y, b.y);
}
bool iseqtrg(point a, point b, point c){
double d1 = len(a,b);
double d2 = len(b,c);
double d3 = len(c,a);
return checkeq(d1,d2)&&checkeq(d2,d3);
}
pair<point, point> possible(point a, point b){
point x1,x2;
point m = {(a.x+b.x)/2,(a.y+b.y)/2};
double l = len(a,b);
double sinx = (b.x-a.x)/l;
double cosx = (b.y-a.y)/l;
double dispx = l * sqrt(3.0/4) * cosx;
double dispy = l*sqrt(3.0/4) * sinx;
x1 = {m.x-dispx,m.y + dispy};
x2 = {m.x + dispx, m.y - dispy};
return {x1,x2};
}
bool findPoint(point *arr, int n, point x){
int st = 0;
int dr = n-1;
while(st <= dr){
int m = (st+dr)/2;
if(checkpoint(x,arr[m]))
return true;
if(x < arr[m]){
dr = m-1;
}
else{
st = m+1;
}
}
return false;
}
int main()
{
int n;
fin>>n;
for(int i = 0; i < 1500; i++){
for(int j = 0; j < 1500; j++){
for(int k = 0; k < 20; k++){
int a = 324423;
a = a*a;
a= a*a;
}
}
}
point arr[n];
double x,y;
for(int i = 0; i < n; i++){
fin >> x >> y;
arr[i] = {x,y};
}
sort(arr,arr+n);
int cnt = 0;
for(int i = 0; i < n-1; i++){
for(int j = i+1; j < n; j++){
pair<point, point> p = possible(arr[i], arr[j]);
point x1 = p.first, x2 = p.second;
if(findPoint(arr, n, x1))
cnt ++;
if(findPoint(arr, n, x2))
cnt++;
}
}
fout<<cnt/3;
return 0;
}