Bobo wants to count the number of matrices $A$ that satisfy the following conditions:
- Matrix $A$ has $n$ rows and $m$ columns, and every element is a positive integer. The element in the $i$-th row and $j$-th column is denoted by $A_{i, j}$.
- $A_{1, 1} = 2018$.
- For all $2 \leq i \leq n, 1 \leq j \leq m$, $A_{i, j}$ is a divisor of $A_{i - 1, j}$.
- For all $1 \leq i \leq n, 2 \leq j \leq m$, $A_{i, j}$ is a divisor of $A_{i, j - 1}$.
Since the number of such matrices $A$ can be very large, Bobo only wants to find the number of such matrices modulo $(10^9+7)$.
Input
The input contains multiple test cases. Process until the end of the file.
Each test case contains two integers $n$ and $m$.
Output
For each test case, output one integer representing the number of such matrices modulo $(10^9+7)$.
Examples
Input 1
1 1 1 2 2 2 2 3 2000 2000
Output 1
1 4 25 81 570806941
Note
For the second test case ($n = 1, m = 2$), the matrices $A$ that satisfy the conditions are $(2018, 2018), (2018, 1009), (2018, 2), (2018, 1)$, totaling $4$ possibilities.
Constraints
- $1 \leq n, m \leq 2000$
- The number of test cases does not exceed $10^5$.