#include<bits/stdc++.h>
using namespace std;
int main(){
	int t,n;
	cin>>t;
	while(t--){
		cin>>n;
		int l=1,r=3*n;
		for(int i=1;i<=n;i++){
			cout<<l<<" "<<r-1<<" "<<r<<" ";
			l++,r-=2;
		}
		cout<<"\n";
	}
	return 0;
}