#include <iostream>
#include <stdio.h>
#include <string.h>
#include <algorithm>

using namespace std;

long long t , n , x;
char a[100];

inline char cal( int x )
{
    if( x == 0 ) return 'R';
    if( x == 1 ) return 'G';
    return 'B';
}

int main()
{
    cin >> t;
    while( t-- )
    {
        memset( a , 0 , sizeof( a ) );
        cin >> n >> x;
        for( register int i = 1 ; i <= n ; i++ ) a[i - 1] = cal( x % 3 ) , x /= 3;
        reverse( a , a + n );
        cout << a << endl;
    }
    return 0;
}