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: //
  // Source code recreated from a .class file by IntelliJ IDEA
  // (powered by Fernflower decompiler)
  //
  
  import java.io.BufferedWriter;
  import java.io.DataInputStream;
  import java.io.FileInputStream;
  import java.io.IOException;
  import java.io.OutputStreamWriter;
  import java.util.*;
  
  public class CFB {
      static CFB.Reader sc = new CFB.Reader();
      static BufferedWriter bw;
      static int team1;
      static int team2;
      static int minkicks;
  
      public CFB() {
      }
  
      public static void main(String[] args) throws IOException {
          Scanner sc=new Scanner(System.in);
          int  t=sc.nextInt();
          long mod=1000000007;
          for(int i=0;i<t;i++){
              long n=sc.nextLong();
              long k=sc.nextLong();
              long copk=k;
              long ans=0;
              long c=0;
              while (copk!=0){
                  long rem=copk%2;
                  if(rem==1){
                      ans+=power(n,c,mod);
                      ans=ans%mod;
                  }
                  copk/=2;
                  c++;
  
              }
              System.out.println(ans);
  
          }
  
  
  
  
  
  
  
  
          bw.flush();
          bw.close();
      }
  
  
  
      public static class Coffee{
          int st,en;
         public Coffee(int st,int en){
             this.st=st;
             this.en=en;
         }
      }
  
      public static int checker(int a) {
          if (a % 2 == 0) {
              return 1;
          } else {
              byte b;
              do {
                  b = 2;
              } while(a + b != (a ^ b));
  
              return b;
          }
      }
  
      public static boolean checkPrime(int n) {
          if (n != 0 && n != 1) {
              for(int j = 2; j * j <= n; ++j) {
                  if (n % j == 0) {
                      return false;
                  }
              }
  
              return true;
          } else {
              return false;
          }
      }
  
      public static void dfs1(List<List<Integer>> g, boolean[] visited, Stack<Integer> stack, int num) {
          visited[num] = true;
          Iterator var4 = ((List)g.get(num)).iterator();
  
          while(var4.hasNext()) {
              Integer integer = (Integer)var4.next();
              if (!visited[integer]) {
                  dfs1(g, visited, stack, integer);
              }
          }
  
          stack.push(num);
      }
  
      public static void dfs2(List<List<Integer>> g, boolean[] visited, List<Integer> list, int num, int c, int[] raj) {
          visited[num] = true;
          Iterator var6 = ((List)g.get(num)).iterator();
  
          while(var6.hasNext()) {
              Integer integer = (Integer)var6.next();
              if (!visited[integer]) {
                  dfs2(g, visited, list, integer, c, raj);
              }
          }
  
          raj[num] = c;
          list.add(num);
      }
  
      public static int inputInt() throws IOException {
          return sc.nextInt();
      }
  
      public static long inputLong() throws IOException {
          return sc.nextLong();
      }
  
      public static double inputDouble() throws IOException {
          return sc.nextDouble();
      }
  
      public static String inputString() throws IOException {
          return sc.readLine();
      }
  
      public static void print(String a) throws IOException {
          bw.write(a);
      }
  
      public static void printSp(String a) throws IOException {
          bw.write(a + " ");
      }
  
      public static void println(String a) throws IOException {
          bw.write(a + "\n");
      }
  
      public static long getAns(int[] ar, int c, long[][] dp, int i, int sign) {
          if (i < 0) {
              return 1L;
          } else if (c <= 0) {
              return 1L;
          } else {
              dp[i][c] = Math.max(dp[i][c], Math.max((long)ar[i] * getAns(ar, c - 1, dp, i - 1, sign), getAns(ar, c, dp, i - 1, 1)));
              return dp[i][c];
          }
      }
  
      public static long power(long a, long b, long c) {
          long ans;
          for(ans = 1L; b != 0L; b /= 2L) {
              if (b % 2L == 1L) {
                  ans *= a;
                  ans %= c;
              }
  
              a *= a;
              a %= c;
          }
  
          return ans;
      }
  
      public static long power1(long a, long b, long c) {
          long ans;
          for(ans = 1L; b != 0L; b /= 2L) {
              if (b % 2L == 1L) {
                  ans = multiply(ans, a, c);
              }
  
              a = multiply(a, a, c);
          }
  
          return ans;
      }
  
      public static long multiply(long a, long b, long c) {
          long res = 0L;
  
          for(a %= c; b > 0L; b /= 2L) {
              if (b % 2L == 1L) {
                  res = (res + a) % c;
              }
  
              a = (a + a) % c;
          }
  
          return res % c;
      }
  
      public static long totient(long n) {
          long result = n;
  
          for(long i = 2L; i * i <= n; ++i) {
              if (n % i == 0L) {
                  while(n % i == 0L) {
                      n /= i;
                  }
  
                  result -= result / i;
              }
          }
  
          if (n > 1L) {
              result -= result / n;
          }
  
          return result;
      }
  
      public static long gcd(long a, long b) {
          return b == 0L ? a : gcd(b, a % b);
      }
  
      public static boolean[] primes(int n) {
          boolean[] p = new boolean[n + 1];
          p[0] = false;
          p[1] = false;
  
          int i;
          for(i = 2; i <= n; ++i) {
              p[i] = true;
          }
  
          for(i = 2; i * i <= n; ++i) {
              if (p[i]) {
                  for(int j = i * i; j <= n; j += i) {
                      p[j] = false;
                  }
              }
          }
  
          return p;
      }
  
      public String LargestEven(String S) {
          int[] count = new int[10];
  
          int num;
          for(num = 0; num < S.length(); ++num) {
              ++count[S.charAt(num) - 48];
          }
  
          num = -1;
  
          for(int i = 0; i <= 8; i += 2) {
              if (count[i] > 0) {
                  num = i;
                  break;
              }
          }
  
          StringBuilder ans = new StringBuilder();
  
          for(int i = 9; i >= 0; --i) {
              int j;
              if (i != num) {
                  for(j = 1; j <= count[i]; ++j) {
                      ans.append(i);
                  }
              } else {
                  for(j = 1; j <= count[num] - 1; ++j) {
                      ans.append(num);
                  }
              }
          }
  
          if (num != -1 && count[num] > 0) {
              ans.append(num);
          }
  
          return ans.toString();
      }
  
      static {
          bw = new BufferedWriter(new OutputStreamWriter(System.out));
          team1 = 0;
          team2 = 0;
          minkicks = 10;
      }
  
      public static class Score {
          int l;
          String s;
  
          public Score(int l, String s) {
              this.l = l;
              this.s = s;
          }
      }
  
      public static class Ath {
          int r1;
          int r2;
          int r3;
          int r4;
          int r5;
          int index;
  
          public Ath(int r1, int r2, int r3, int r4, int r5, int index) {
              this.r1 = r1;
              this.r2 = r2;
              this.r3 = r3;
              this.r4 = r4;
              this.r5 = r5;
              this.index = index;
          }
      }
  
      static class Reader {
          private final int BUFFER_SIZE = 65536;
          private DataInputStream din;
          private byte[] buffer;
          private int bufferPointer;
          private int bytesRead;
  
          public Reader() {
              this.din = new DataInputStream(System.in);
              this.buffer = new byte[65536];
              this.bufferPointer = this.bytesRead = 0;
          }
  
          public Reader(String file_name) throws IOException {
              this.din = new DataInputStream(new FileInputStream(file_name));
              this.buffer = new byte[65536];
              this.bufferPointer = this.bytesRead = 0;
          }
  
          public String readLine() throws IOException {
              byte[] buf = new byte[64];
  
              int cnt;
              byte c;
              for(cnt = 0; (c = this.read()) != -1 && c != 10; buf[cnt++] = (byte)c) {
              }
  
              return new String(buf, 0, cnt);
          }
  
          public int nextInt() throws IOException {
              int ret = 0;
  
              byte c;
              for(c = this.read(); c <= 32; c = this.read()) {
              }
  
              boolean neg = c == 45;
              if (neg) {
                  c = this.read();
              }
  
              do {
                  ret = ret * 10 + c - 48;
              } while((c = this.read()) >= 48 && c <= 57);
  
              return neg ? -ret : ret;
          }
  
          public long nextLong() throws IOException {
              long ret = 0L;
  
              byte c;
              for(c = this.read(); c <= 32; c = this.read()) {
              }
  
              boolean neg = c == 45;
              if (neg) {
                  c = this.read();
              }
  
              do {
                  ret = ret * 10L + (long)c - 48L;
              } while((c = this.read()) >= 48 && c <= 57);
  
              return neg ? -ret : ret;
          }
  
          public double nextDouble() throws IOException {
              double ret = 0.0D;
              double div = 1.0D;
  
              byte c;
              for(c = this.read(); c <= 32; c = this.read()) {
              }
  
              boolean neg = c == 45;
              if (neg) {
                  c = this.read();
              }
  
              do {
                  ret = ret * 10.0D + (double)c - 48.0D;
              } while((c = this.read()) >= 48 && c <= 57);
  
              if (c == 46) {
                  while((c = this.read()) >= 48 && c <= 57) {
                      ret += (double)(c - 48) / (div *= 10.0D);
                  }
              }
  
              return neg ? -ret : ret;
          }
  
          private void fillBuffer() throws IOException {
              this.bytesRead = this.din.read(this.buffer, this.bufferPointer = 0, 65536);
              if (this.bytesRead == -1) {
                  this.buffer[0] = -1;
              }
  
          }
  
          private byte read() throws IOException {
              if (this.bufferPointer == this.bytesRead) {
                  this.fillBuffer();
              }
  
              return this.buffer[this.bufferPointer++];
          }
  
          public void close() throws IOException {
              if (this.din != null) {
                  this.din.close();
              }
          }
      }
  }
  