//#pragma comment(linker, "/STACK:1024000000,1024000000")
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<map>
#include<cmath>
#include<queue>
#include<stack>
#include<ctime>
#include<vector>
#include<set>
#include<cfloat>
#include<sstream>

using namespace std;

const int maxn=100250;
const int INF=999999999;
//const float eps = 0.00000001;
const int mod=1000000007;
//const int mod=100000000;
const int VM=1220;
const int EM=1000010;
//const int N=120;
//const double PI=3.14159;
const double PI=3.14159265359;
const double eps=1e-6;

typedef pair<int,int> P;
//int dir[4][2]={{-1,0},{1,0},{0,-1},{0,1}};
//int dir[4][2]={{0,1},{0,-1},{-1,0},{1,0}};
int dir[4][2]={{1,0},{0,-1},{-1,0},{0,1}};

/**

*/



int main(){

    //freopen("input.txt","r",stdin);

    //freopen("out.txt","w",stdout);

    int t,m;
    long long n;
    cin>>t;
    char str[3]={'R','G','B'};
    while(t--){
        cin>>m>>n;
        if(n==1){
            for(int i=1;i<m;i++){
                printf("R");
            }
            printf("G\n");
            continue;
        }
        if(n==2){
            for(int i=1;i<m;i++){
                printf("R");
            }
            printf("B\n");
            continue;
        }
        char res[50];
        int len=30;
        for(int i=m;i>=1;i--){
            res[i]=str[n%3];
            n/=3;
        }
        for(int i=1;i<=m;i++)
            printf("%c",res[i]);
        printf("\n");
    }

    return 0;
}