description: Theofanis really likes sequences of positive integers, thus his teacher (Yeltsa Kcir) gave him a problem about a sequence that consists of only special numbers.
  
  Let's call a positive number special if it can be written as a sum of different non-negative powers of n. For example, for n = 4 number 17 is special, because it can be written as 4^0 + 4^2 = 1 + 16 = 17, but 9 is not.
  
  Theofanis asks you to help him find the k-th special number if they are sorted in increasing order. Since this number may be too large, output it modulo 10^9+7.
  
  Input
  
  The first line contains a single integer t (1 ≤ t ≤ 10^4) — the number of test cases.
  
  The first and only line of each test case contains two integers n and k (2 ≤ n ≤ 10^9; 1 ≤ k ≤ 10^9).
  
  Output
  
  For each test case, print one integer — the k-th special number in increasing order modulo 10^9+7.
  
  Example
  
  Input
  
  
  3
  3 4
  2 12
  105 564
  
  
  Output
  
  
  9
  12
  3595374
  
  Note
  
  For n = 3 the sequence is [1,3,4,9...]
solution: 
  
  import java.io.*;
  import java.math.*;
  import java.util.*;
  
  
  // @author : Dinosparton 
  
  public class test {
  	 
  	   static class Pair{ 
  		   long x;
  		   long y;
  		   
  		   Pair(long x,long y){ 
  			   this.x = x;
  			   this.y = y;
  			   
  		   }
  	   }
  	  
  	   static class Sort implements Comparator<Pair>
  	   {
  
  	       @Override
  	       public int compare(Pair a, Pair b)
  	       {
  	           if(a.x!=b.x)
  	           {
  	               return (int)(a.x - b.x);
  	           }
  	           else
  	           {
  	               return (int)(a.y-b.y);
  	           }
  	       }
  	   }
  	   
  	   static class Compare { 
  		   
  		     void compare(Pair arr[], int n) 
  		    { 
  		        // Comparator to sort the pair according to second element 
  		        Arrays.sort(arr, new Comparator<Pair>() { 
  		            @Override public int compare(Pair p1, Pair p2) 
  		            { 
  		            	if(p1.x!=p2.x) {
  		                return (int)(p1.x - p2.x); 
  		            	}
  		            	else { 
  		            		return (int)(p1.y - p2.y);
  		            	}
  		            } 
  		        }); 
  		  
  //		        for (int i = 0; i < n; i++) { 
  //		            System.out.print(arr[i].x + " " + arr[i].y + " "); 
  //		        } 
  //		        System.out.println(); 
  		    } 
  		} 
  	 
  	   static class Scanner {
  	        BufferedReader br;
  	        StringTokenizer st;
  	 
  	        public Scanner()
  	        {
  	            br = new BufferedReader(
  	                new InputStreamReader(System.in));
  	        }
  	 
  	        String next()
  	        {
  	            while (st == null || !st.hasMoreElements()) {
  	                try {
  	                    st = new StringTokenizer(br.readLine());
  	                }
  	                catch (IOException e) {
  	                    e.printStackTrace();
  	                }
  	            }
  	            return st.nextToken();
  	        }
  	 
  	        int nextInt() { return Integer.parseInt(next()); }
  	 
  	        long nextLong() { return Long.parseLong(next()); }
  	 
  	        double nextDouble()
  	        {
  	            return Double.parseDouble(next());
  	        }
  	 
  	        String nextLine()
  	        {
  	            String str = "";
  	            try {
  	                str = br.readLine();
  	            }
  	            catch (IOException e) {
  	                e.printStackTrace();
  	            }
  	            return str;
  	        }
  	    }
  	 
  	 static long mod = (long)1e9 + 7; 
  	   public static void main(String args[]) throws Exception { 
  		
  		   
  		   Scanner sc = new Scanner();
  		   StringBuilder res = new StringBuilder();
  		
  		   int tc = sc.nextInt();
  		   
  		   while(tc-->0) { 
  			
  			   long n = sc.nextLong();
  			   long k = sc.nextLong();
  			   
  			    long base = 1;
  		        long ans = 0;
  		        
  		        for(int i=0;i<31;i++){
  		            if((k & (1<<i)) != 0){
  		                ans = (ans + base) % mod;
  		            }
  		            base *= n;
  		            base %= mod;
  		        }
  		        res.append(ans+"\n");
  		   }
  		   System.out.println(res);
  	   }
  }  
  
  
  
  
  