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: //---#ON_MY_WAY---
  import static java.lang.Math.*;
  import java.io.*;
  import java.math.*;
  import java.util.*;
  
  public class apples {
  	static class pair {
  		int x, y;
  
  		public pair(int a, int b) {
  			x = a;
  			y = b;
  		}
  	}
  
  	static FastReader x = new FastReader();
  	static OutputStream outputStream = System.out;
  	static PrintWriter out = new PrintWriter(outputStream);
  
  	/*---------------------------------------CODE STARTS HERE-------------------------*/
  	public static void main(String[] args) throws NumberFormatException, IOException {
  		long startTime = System.nanoTime();
  		int mod = 1000000007;
  		int t = x.nextInt();
  		StringBuilder str = new StringBuilder();
  		while (t > 0) {
  			int n = x.nextInt();
  			int k = x.nextInt();
  			long ans = 0;
  			String s = Integer.toBinaryString(k);
  			int c = 0;
  			for(int i = s.length()-1; i >= 0; i--) {
  				if(s.charAt(i)=='1') {
  					long res = 1;
  					for(int j = 0; j < c; j++) {
  						res *= n;
  						res %= mod;
  					}
  					ans += res;
  					ans %= mod;
  				}
  				c++;
  			}
  			str.append(ans);
  			str.append("\n");
  			t--;
  		}
  		out.println(str);
  		out.flush();
  		long endTime = System.nanoTime();
  		//System.out.println((endTime-startTime)/1000000000.0);
  	}
  
  	/*--------------------------------------------FAST I/O--------------------------------*/
  	static class FastReader {
  		BufferedReader br;
  		StringTokenizer st;
  
  		public FastReader() {
  			br = new BufferedReader(new InputStreamReader(System.in));
  		}
  
  		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;
  		}
  
  		char nextchar() {
  			char ch = ' ';
  			try {
  				ch = (char) br.read();
  			} catch (IOException e) {
  				e.printStackTrace();
  			}
  			return ch;
  		}
  	}
  
  	/*--------------------------------------------BOILER PLATE---------------------------*/
  	static int[] readarr(int n) {
  		int arr[] = new int[n];
  		for (int i = 0; i < n; i++) {
  			arr[i] = x.nextInt();
  		}
  		return arr;
  	}
  
  	static int[] sortint(int a[]) {
  		ArrayList<Integer> al = new ArrayList<>();
  		for (int i : a) {
  			al.add(i);
  		}
  		Collections.sort(al);
  		for (int i = 0; i < a.length; i++) {
  			a[i] = al.get(i);
  		}
  		return a;
  	}
  
  	static long[] sortlong(long a[]) {
  		ArrayList<Long> al = new ArrayList<>();
  		for (long i : a) {
  			al.add(i);
  		}
  		Collections.sort(al);
  		for (int i = 0; i < al.size(); i++) {
  			a[i] = al.get(i);
  		}
  		return a;
  	}
  
  	static long pow(long x, long y) {
  		long result = 1;
  		while (y > 0) {
  			if (y % 2 == 0) {
  				x = x * x;
  				y = y / 2;
  			} else {
  				result = result * x;
  				y = y - 1;
  			}
  		}
  		return result;
  	}
  
  	static int[] revsort(int a[]) {
  		ArrayList<Integer> al = new ArrayList<>();
  		for (int i : a) {
  			al.add(i);
  		}
  		Collections.sort(al, Comparator.reverseOrder());
  		for (int i = 0; i < a.length; i++) {
  			a[i] = al.get(i);
  		}
  		return a;
  	}
  
  	static int[] gcd(int a, int b, int ar[]) {
  		if (b == 0) {
  			ar[0] = a;
  			ar[1] = 1;
  			ar[2] = 0;
  			return ar;
  		}
  		ar = gcd(b, a % b, ar);
  		int t = ar[1];
  		ar[1] = ar[2];
  		ar[2] = t - (a / b) * ar[2];
  		return ar;
  	}
  
  	static boolean[] esieve(int n) {
  		boolean p[] = new boolean[n + 1];
  		Arrays.fill(p, true);
  		for (int i = 2; i * i <= n; i++) {
  			if (p[i] == true) {
  				for (int j = i * i; j <= n; j += i) {
  					p[j] = false;
  				}
  			}
  		}
  		return p;
  	}
  
  	static ArrayList<Integer> primes(int n) {
  		boolean p[] = new boolean[n + 1];
  		ArrayList<Integer> al = new ArrayList<>();
  		Arrays.fill(p, true);
  		int i = 0;
  		for (i = 2; i * i <= n; i++) {
  			if (p[i] == true) {
  				al.add(i);
  				for (int j = i * i; j <= n; j += i) {
  					p[j] = false;
  				}
  			}
  		}
  		for (i = i; i <= n; i++) {
  			if (p[i] == true) {
  				al.add(i);
  			}
  		}
  		return al;
  	}
  
  	static int etf(int n) {
  		int res = n;
  		for (int i = 2; i * i <= n; i++) {
  			if (n % i == 0) {
  				res /= i;
  				res *= (i - 1);
  				while (n % i == 0) {
  					n /= i;
  				}
  			}
  		}
  		if (n > 1) {
  			res /= n;
  			res *= (n - 1);
  		}
  		return res;
  	}
  
  	static int gcd(int a, int b) {
  		if (a == 0) {
  			return b;
  		}
  		return gcd(b % a, a);
  	}
  
  	static long gcd(long a, long b) {
  		if (a == 0) {
  			return b;
  		}
  		return gcd(b % a, a);
  	}
  }