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.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.io.File;
  import java.io.*;
  import java.util.*;
  
  public class Main {
  
      // static final File ip = new File("input.txt");
      // static final File op = new File("output.txt");
      // static {
      //     try {
      //         System.setOut(new PrintStream(op));
      //         System.setIn(new FileInputStream(ip));
      //     } catch (Exception e) {
      //     }
      // }
  
      static void block(long x, long n) {
          ArrayList<Long> v = new ArrayList<Long>();
          long sum = 0;
          while (x > 0) {
              v.add((long) x % 2);
              x = x / 2;
          }
          for (int i = 0; i < v.size(); i++) {
              if (v.get(i) == 1) {
                  // System.out.print(v.get(i) + " ");
                  sum = (sum + power(n, i,1000000007)) %1000000007;
              }
          }
          System.out.println(sum);
      }
  
      public static void main(String[] args) {
          FastReader sc = new FastReader();
          int test = sc.nextInt();
          while (test-- != 0) {
              long n = sc.nextLong();
              long k = sc.nextLong();
              block(k, n);
  
          }
      }
  
      static long power(long x, long y, long p) {
          long res = 1;
          x = x % p;
          if (x == 0)
              return 0;
          while (y > 0) {
              if ((y & 1) != 0)
                  res = (res * x) % p;
              y = y >> 1;
              x = (x * x) % p;
          }
          return res;
      }
  
      public static int countSetBits(long number) {
          int count = 0;
          while (number > 0) {
              ++count;
              number &= number - 1;
          }
          return count;
      }
  
      private static <T> void swap(int[] a, int i, int j) {
          int tmp = a[i];
          a[i] = a[j];
          a[j] = tmp;
      }
  
      static class pair {
          long a, b;
  
          pair(long x, long y) {
              this.a = x;
              this.b = y;
          }
  
          // public int compare(pair p1, pair p2) {
          // if (p1.a - p2.a > 0)
          // return -1;
          // if (p1.a - p2.a < 0)
          // return 1;
          // return 0;
          // }
      }
  
      static class comparator implements Comparator<pair> {
  
          public int compare(pair p1, pair p2) {
              if (p1.a > p2.a)
                  return 1;
              else if (p1.a < p2.a)
                  return -1;
              // else {
              // if (p1.a > p2.a)
              // return 1;
              // else if (p1.a < p2.a)
              // return -1;
              // }
              return 0;
          }
      }
  
      private static long getSum(int[] array) {
          long sum = 0;
          for (int value : array) {
              sum += value;
          }
          return sum;
      }
  
      private static boolean isPrime(Long x) {
          if (x < 2)
              return false;
          for (long d = 2; d * d <= x; ++d) {
              if (x % d == 0)
                  return false;
          }
          return true;
      }
  
      static int[] reverse(int a[], int n) {
          int i, k, t;
          for (i = 0; i < n / 2; i++) {
              t = a[i];
              a[i] = a[n - i - 1];
              a[n - i - 1] = t;
          }
          return a;
      }
  
      private static boolean isPrimeInt(int x) {
          if (x < 2)
              return false;
          for (int d = 2; d * d <= x; ++d) {
              if (x % d == 0)
                  return false;
          }
          return true;
      }
  
      public static String reverse(String input) {
          StringBuilder str = new StringBuilder("");
  
          for (int i = input.length() - 1; i >= 0; i--) {
              str.append(input.charAt(i));
          }
  
          return str.toString();
      }
  
      private static int[] getPrimes(int n) {
          boolean[] used = new boolean[n + 1];
          used[0] = used[1] = true;
          int size = 0;
          for (int i = 2; i <= n; ++i) {
              if (!used[i]) {
                  ++size;
                  for (int j = 2 * i; j <= n; j += i) {
                      used[j] = true;
                  }
              }
          }
          int[] primes = new int[size];
          for (int i = 0, cur = 0; i <= n; ++i) {
              if (!used[i]) {
                  primes[cur++] = i;
              }
          }
          return primes;
      }
  
      private static long lcm(long a, long b) {
          return a / gcd(a, b) * b;
      }
  
      private static long gcd(long a, long b) {
          return (a == 0 ? b : gcd(b % a, a));
      }
  
      static void sortI(int[] arr) {
          int n = arr.length;
          Random rnd = new Random();
          for (int i = 0; i < n; ++i) {
              int tmp = arr[i];
              int randomPos = i + rnd.nextInt(n - i);
              arr[i] = arr[randomPos];
              arr[randomPos] = tmp;
          }
          Arrays.sort(arr);
      }
  
      static void shuffleList(ArrayList<Long> arr) {
          int n = arr.size();
          Random rnd = new Random();
          for (int i = 0; i < n; ++i) {
              long tmp = arr.get(i);
              int randomPos = i + rnd.nextInt(n - i);
              arr.set(i, arr.get(randomPos));
              arr.set(randomPos, tmp);
          }
      }
  
      static void factorize(long n) {
          int count = 0;
          while (!(n % 2 > 0)) {
              n >>= 1;
  
              count++;
          }
          if (count > 0) {
              // System.out.println("2" + " " + count);
          }
          long i = 0;
          for (i = 3; i <= (long) Math.sqrt(n); i += 2) {
              count = 0;
              while (n % i == 0) {
                  count++;
                  n = n / i;
              }
              if (count > 0) {
                  // System.out.println(i + " " + count);
              }
          }
  
          if (n > 2) {
              // System.out.println(i + " " + count);
          }
      }
  
      static void sortL(long[] arr) {
          int n = arr.length;
          Random rnd = new Random();
          for (int i = 0; i < n; ++i) {
              long tmp = arr[i];
              int randomPos = i + rnd.nextInt(n - i);
              arr[i] = arr[randomPos];
              arr[randomPos] = tmp;
          }
          Arrays.sort(arr);
      }
  
      static class FastReader {
          BufferedReader br;
          StringTokenizer st;
  
          public FastReader() {
              br = new BufferedReader(new InputStreamReader(System.in));
          }
  
          public boolean hasNext() {
              return false;
          }
  
          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;
          }
      }
  }