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.PrintWriter;
  import java.util.StringTokenizer;
  
  public class Solution45 {
  
  	private final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  
  	private final PrintWriter pw = new PrintWriter(System.out);
  
  	public static void main(String[] args) {
  
  		Solution45 solution = new Solution45();
  
  		solution.solveCases();
  		solution.close();
  
  	}
  
  	private void solveCases() {
  
  		int t = readInt();
  		for (int i = 1; i <= t; i++) {
  			pw.println(solve());
  
  		}
  	}
  
  	long modP(int n, int cnt) {
  		long rv = 1;
  		for (int i = 1; i < cnt; i++) {
  			rv *= n;
  			rv %= 1000000007;
  		}
  		return rv;
  	}
  
  	private String solve() {
  		int[] arr = readIntArr();
  		int n = arr[0];
  		int k = arr[1];
  
  		long rv = 0;
  		int cnt = 1;
  	
  		while (k > 0) {
  			if (k % 2 == 1) {
  				rv += modP(n, cnt);
  				rv %= 1000000007;
  				
  			}
  			k >>= 1;
  			cnt++;
  		}
  
  		return "" + rv;
  	}
  
  	private void close() {
  
  		pw.close();
  
  	}
  
  	private String readLine() {
  		String line = null;
  		try {
  			line = br.readLine();
  		} catch (IOException e) {
  			e.printStackTrace();
  		}
  		return line;
  
  	}
  
  	private String readString() {
  		return readLine();
  
  	}
  
  	private long readLong() {
  		return Long.parseLong(readLine());
  	}
  
  	private int readInt() {
  		return Integer.parseInt(readLine());
  	}
  
  	private String[] stringArray() {
  
  		StringTokenizer st = new StringTokenizer(readLine());
  		int n = st.countTokens();
  		String ret[] = new String[n];
  		for (int i = 0; i < n; i++) {
  			ret[i] = st.nextToken();
  		}
  		return ret;
  
  	}
  
  	private int[] readIntArr() {
  		String[] str = stringArray();
  		int arr[] = new int[str.length];
  		for (int i = 0; i < arr.length; i++)
  			arr[i] = Integer.parseInt(str[i]);
  		return arr;
  	}
  
  	private double[] readDoubleArr() {
  		String[] str = stringArray();
  		double arr[] = new double[str.length];
  		for (int i = 0; i < arr.length; i++)
  			arr[i] = Double.parseDouble(str[i]);
  		return arr;
  	}
  
  	private long[] readLongArr() {
  		String[] str = stringArray();
  		long arr[] = new long[str.length];
  		for (int i = 0; i < arr.length; i++)
  			arr[i] = Long.parseLong(str[i]);
  		return arr;
  	}
  
  	private double readDouble() {
  		return Double.parseDouble(readLine());
  	}
  }
  