#include<iostream>
#include<string>
#include<cmath>
#define M 2005
using namespace std;
int n,px[M],py[M];
struct point
{
int flag;
int x;
int y;
struct point *next;
};
struct point *hash[M];
void insert(struct point *h,int xx,int yy)
{
if(h->flag==0)
{
h->flag=1;
h->x=xx;
h->y=yy;
h->next=new struct point;
h->next->flag=0;
}
else
insert(h->next,xx,yy);
}
int find(int xx,int yy)
{
int key;
key=abs((xx*xx+yy)%M);
struct point *h=hash[key];
while(1)
{
if(h->flag==0)
return 0;
if(h->x==xx&&h->y==yy)
return 1;
else h=h->next;
}
}
int main()
{
int i,j,xx,yy,key,ans,x1,y1,x2,y2,x3,y3,x4,y4;
for(i=0;i<M;i++)
hash[i]=new struct point;
while(scanf("%d",&n),n!=0)
{
for(i=0;i<M;i++)
hash[i]->flag=0;
for(i=0;i<n;i++)
{
scanf("%d%d",&xx,&yy);
px[i]=xx;
py[i]=yy;
key=abs((xx*xx+yy)%M);
insert(hash[key],xx,yy);
}
ans=0;
for(i=0;i<n;i++)
for(j=0;j<n;j++)
if(i!=j)
{
x1=px[i];
x2=px[j];
y1=py[i];
y2=py[j];
if(!(x2>x1&&y2>=y1))
continue;
x3=x2+y2-y1;
y3=y2-(x2-x1);
x4=x1+y2-y1;
y4=y1-(x2-x1);
if(find(x3,y3)&&find(x4,y4))
ans++;
}
printf("%d\n",ans);
}
return 0;
}