#include<bits/stdc++.h>
typedef long long ll;
using namespace std;
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(0);cout.tie(0);
	ll t;cin>>t;
	while(t--)
	{
		ll n;cin>>n;
		ll arr[n],pos[1001],neg[1001];
		memset(pos,0,sizeof(pos));
		memset(neg,0,sizeof(neg));
		//map<ll,ll> m;

		for(ll i=0;i<n;i++)
		{
			cin>>arr[i];
			if(arr[i]>=0)
				pos[arr[i]]++;
			else if(arr[i]<0)
			{
				neg[abs(arr[i])]++;
			}
		}
		//cout<<neg[2]<<endl;
		ll ans=0,redundant=0;
		for(ll i=-1e3;i<=1e3;i++)
		{
			for(ll j=-1e3;j<=1e3;j++)
			{
				ll t1,t2;
				if(i<0)
					t1=neg[abs(i)];
				else
					t1=pos[i];

				if(j<0)
					t2=neg[abs(j)];
				else
					t2=pos[j];


				//ll t1=m[i],t2=m[j];
				if(i==j)
				{
					ans=ans+((t1)*(t1-1))/2;
				}
				else
				{
					if((i+j)%2==0)
					{
						ll temp=(i+j)/2;
						if(temp<0)
						{
							if(neg[abs(temp)]!=0)
							{
								ans=ans+t1*t2;
								redundant=redundant+t1*t2;
							}
						}
						else if(temp>=0)
						{						
							if(pos[temp]!=0)
							{
								ans=ans+t1*t2;
								redundant=redundant+t1*t2;
							}
						}
						
					}
				}
			}
		}
		//cout<<"redundant is "<<redundant<<endl;
		ans=ans-(redundant/2);
		cout<<ans<<endl;
	}
}