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: # Sujith
  from sys import stdin,stdout,setrecursionlimit
  from io import BytesIO, IOBase
  # from heapq import heappush as push,heappop as hp,heapify as h
  # from math import gcd,floor,sqrt,ceil
  # from collections import Counter,deque as dq
  # from itertools import accumulate as acc,permutations as perm
  # from bisect import bisect_left as bl,bisect_right as br,bisect as bis
  
  setrecursionlimit(10000)
  
  class FastIO(IOBase):
      newlines = 0
  
      def __init__(self, file):
          import os
          self.os = os
          self._fd = file.fileno()
          self.buffer = BytesIO()
          self.writable = "x" in file.mode or "r" not in file.mode
          self.write = self.buffer.write if self.writable else None
          self.BUFSIZE = 8192
  
      def read(self):
          while True:
              a = self.os.read(self._fd, max(self.os.fstat(self._fd).st_size, self.BUFSIZE))
              if not a:
                  break
              ptr = self.buffer.tell()
              self.buffer.seek(0, 2), self.buffer.write(a), self.buffer.seek(ptr)
          self.newlines = 0
          return self.buffer.read()
  
      def readline(self):
          while self.newlines == 0:
              a = self.os.read(self._fd, max(self.os.fstat(self._fd).st_size, self.BUFSIZE))
              self.newlines = a.count(b"\n") + (not a)
              ptr = self.buffer.tell()
              self.buffer.seek(0, 2), self.buffer.write(a), self.buffer.seek(ptr)
          self.newlines -= 1
          return self.buffer.readline()
  
      def flush(self):
          if self.writable:
              self.os.write(self._fd, self.buffer.getvalue())
              self.buffer.truncate(0), self.buffer.seek(0)
  
  
  class IOWrapper(IOBase):
      def __init__(self, file):
          self.buffer = FastIO(file)
          self.flush = self.buffer.flush
          self.writable = self.buffer.writable
          self.write = lambda s: self.buffer.write(s.encode("ascii"))
          self.read = lambda: self.buffer.read().decode("ascii")
          self.readline = lambda: self.buffer.readline().decode("ascii")
  
  
  stdin, stdout = IOWrapper(stdin), IOWrapper(stdout)
  input = lambda: stdin.readline().rstrip("\r\n")
  
  # inf = float('inf')
  # ninf = float('-inf')
  # abc = 'abcdefghijklmnopqrstuvwxyz'
  inp = lambda: int(input())
  st = lambda: input().strip()
  jn = lambda x,l: x.join(map(str,l))
  int_arr = lambda : list(map(int,input().strip().split()))
  str_arr = lambda :list(map(str,input().split()))
  get_str = lambda : map(str,input().strip().split())
  get_int = lambda: map(int,input().strip().split())
  get_float = lambda : map(float,input().strip().split())
  
  mod = 1000000007
  
  def binpow(a,b,mod):
      a %= mod
      res = 1
      while b > 0:
          if b & 1:
              res = (res * a) % mod
          a = (a * a) % mod
          b >>= 1
      return res 
  
  #main()
  for _ in range(inp()):
      n,k = get_int()
  
      val = bin(k)[2:]
      tot = 0
      l = len(val)
      for i in range(l-1,-1,-1):
          if val[i] == '1':
              tot = (tot + binpow(n,l - 1 - i,mod)) % mod
      print(tot)
  