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.BigDecimal;
  import java.math.BigInteger;
  import java.math.MathContext;
  import java.math.RoundingMode;
  import java.util.*;
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.util.Collections;
  import java.io.InputStreamReader;
  import static java.lang.Math.*;
  import static java.lang.System.*;
  
  public class Main1 {
  static long mod= (long) 1e9 + 7 ;
          static long solver(int n , int level){
              if (n == level)return 16 ;
              long ans =  (solver(n , level+1) ) ;
              if (ans > mod)ans %= mod ;
              ans = (ans*ans) ;
              if (ans > mod)ans %= mod ;
             ans = ans*16 ;
              if (ans > mod)ans %= mod ;
              return ans ;
  
          }
  
  
  
  
  
      public static void main(String[] args) throws IOException {
  
          try {
  //             Scanner in = new Scanner(System.in) ;
          FastScanner in = new FastScanner();
          PrintWriter out = new PrintWriter(System.out);
  
  
  
              int t = in.nextInt() ;
              while (t-- > 0){
                  int n = in.nextInt() ;
                  int k = in.nextInt() ;
                  String s = Integer.toBinaryString(k) ;
  
                  long ans = 0 ;
                  long pow = 1 ;
                  long mod = (long) 1e9 + 7 ;
  
                  for (int i = s.length()-1 ; i>=0 ; i--){
                      if (s.charAt(i) == '1'){
                          ans = (ans+ pow)%mod ;
                      }
  
                      pow = (pow*n)%mod ;
  
                  }
  
                  System.out.println(ans);
  
  
              }
  
  
  
  
  
  
  
  
  
  
  
  
  
              out.flush();
              out.close();
  
  
          } catch (Exception e) {
              return;
          }
  
  }
  
      static long gcd(long a, long b) {
          return (b == 0) ? a : gcd(b, a % b);
      }
  
      static int gcd(int a, int b) {
          return (b == 0) ? a : gcd(b, a % b);
      }
  
      static void sort(int ar[]) {
          int n = ar.length;
          ArrayList<Integer> a = new ArrayList<>();
          for (int i = 0; i < n; i++)
              a.add(ar[i]);
          Collections.sort(a);
          for (int i = 0; i < n; i++)
              ar[i] = a.get(i);
      }
  
      static void sort1(long ar[]) {
          int n = ar.length;
          ArrayList<Long> a = new ArrayList<>();
          for (int i = 0; i < n; i++)
              a.add(ar[i]);
          Collections.sort(a);
          for (int i = 0; i < n; i++)
              ar[i] = a.get(i);
      }
  
      static long ncr(long n, long r, long mod) {
          if (r == 0)
              return 1;
          long val = ncr(n - 1, r - 1, mod);
          val = (n * val) % mod;
          val = (val * modInverse(r, mod)) % mod;
          return val;
      }
  
      static long fast_pow(long base, long n, long M) {
          if (n == 0)
              return 1;
          if (n == 1)
              return base % M;
          long halfn = fast_pow(base, n / 2, M);
          if (n % 2 == 0)
              return (halfn * halfn) % M;
          else
              return (((halfn * halfn) % M) * base) % M;
      }
  
      static long modInverse(long n, long M) {
          return fast_pow(n, M - 2, M);
      }
  
  
      static class FastScanner {
          BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
          StringTokenizer st = new StringTokenizer("");
  
          String next() {
              while (!st.hasMoreTokens())
                  try {
                      st = new StringTokenizer(br.readLine());
                  } catch (IOException e) {
                      e.printStackTrace();
                  }
              return st.nextToken();
          }
  
          int nextInt() {
              return Integer.parseInt(next());
          }
  
          int[] readArray(int n) {
              int[] a = new int[n];
              for (int i = 0; i < n; i++) a[i] = nextInt();
              return a;
          }
  
  
          long nextLong() {
              return Long.parseLong(next());
          }
      }
  
  
  }
  
  
  
  
  
  
  
  