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: #include <bits/stdc++.h>
  using namespace std;
  template <typename T>
  ostream& operator<<(ostream& os, vector<T>& v) {
    if (v.size() == 0) {
      os << "empty vector\n";
      return os;
    }
    for (auto element : v) os << element << " ";
    return os;
  }
  template <typename T, typename second>
  ostream& operator<<(ostream& os, pair<T, second>& p) {
    os << "(" << p.first << ", " << p.second << ")";
    return os;
  }
  template <typename T>
  ostream& operator<<(ostream& os, set<T>& v) {
    if (v.size() == 0) {
      os << "empty set\n";
      return os;
    }
    auto endit = v.end();
    endit--;
    os << "[";
    for (auto it = v.begin(); it != v.end(); it++) {
      os << *it;
      if (it != endit) os << ", ";
    }
    os << "]";
    return os;
  }
  template <typename T>
  ostream& operator<<(ostream& os, multiset<T>& v) {
    if (v.size() == 0) {
      os << "empty multiset\n";
      return os;
    }
    auto endit = v.end();
    endit--;
    os << "[";
    for (auto it = v.begin(); it != v.end(); it++) {
      os << *it;
      if (it != endit) os << ", ";
    }
    os << "]";
    return os;
  }
  template <typename T, typename second>
  ostream& operator<<(ostream& os, map<T, second>& v) {
    if (v.size() == 0) {
      os << "empty map\n";
      return os;
    }
    auto endit = v.end();
    endit--;
    os << "{";
    for (auto it = v.begin(); it != v.end(); it++) {
      os << "(" << (*it).first << " : " << (*it).second << ")";
      if (it != endit) os << ", ";
    }
    os << "}";
    return os;
  }
  template <typename T>
  ostream& operator<<(ostream& os, vector<vector<T>>& v) {
    for (auto& subv : v) {
      for (auto& e : subv) os << e << " ";
      os << "\n";
    }
    return os;
  }
  bool do_debug = false;
  void Runtime_Terror() {
    long long n, k;
    cin >> n >> k;
    vector<long long> v;
    long long cur = 1;
    for (long long i = 0; i < 35; i++) {
      v.push_back(cur);
      cur *= n;
      cur %= 1000000007;
    }
    vector<long long> bits;
    for (long long i = 0; i < 35; i++) {
      if (k & (1ll << i))
        bits.push_back(1);
      else
        bits.push_back(0);
    };
    ;
    long long ans = 0;
    for (long long i = 0; i < 35; i++) {
      if (bits[i]) {
        ans += v[i];
        ans %= 1000000007;
      }
    }
    cout << ans << "\n";
  }
  int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int t = 1;
    cin >> t;
    for (long long i = 0; i < t; i++) Runtime_Terror();
    return 0;
  }
  