#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<queue>
#include<vector>
typedef long long ll;
using namespace std;
void solve(){
    int t;
    ll m,n;
    scanf("%d",&t);
    while(t--){
      char s[40];
        cin>>m>>n;
        ll a;
        for(int i = m-1; i>=0; i--){
            a = n % 3;
            n = n / 3;
            if(a == 0) s[i] = 'R';
            else if(a == 1) s[i] = 'G';
            else s[i] = 'B';
        }
       for(int i = 0; i<m; i++) printf("%c",s[i]);
       printf("\n");
    }
}
int main()
{
    solve();
    return 0;
}