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: n= int(input())
  a = []
  for i in range(n):
      b= []
      y= 0
      x = list(map(int,input().split()))
      while x[1] > 0 :
        for k in range(10**7):
          if x[1]< 2**k:
              b.append(k-1)
              x[1] = x[1] - (2**(k-1))
              break
   
      for j in range(len(b)):
               y += x[0]**b[j]
      if y > (10**9)+7:
          y = y%((10**9)+7)
   
      a.append(y)
  for i in range(n):
   print(a[i])