#include <algorithm>
#include <iostream> 
#include <cstring>
#include <cstdlib>
#include <cstdio>
#include <cmath>
#include <stack>
using namespace std;
typedef long long ll;
const int maxn = 1e3 + 10;


int main(){
    int t;
    scanf("%d", &t);
    while(t--) {
        ll n, m;
        stack<char> s;
        scanf("%I64d%I64d", &m, &n);
        ll k = n;
        while(k) {
            k %= 3;
            if(k == 0) s.push('R'); 
            else if(k == 1) s.push('G');
            else s.push('B');
            if(s.size() >= m) break;
            n /= 3;
            k = n;
        }
        for(int i = 0; i < m-s.size(); i++) 
            printf("R");
        while(!s.empty()){
            printf("%c", s.top());
            s.pop();
        }
        printf("\n");
    }
    return 0;
}