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Link with Balls

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 262144/262144 K (Java/Others)
Total Submission(s): 559    Accepted Submission(s): 319


Problem Description
There were a lot of balls in the factory of Ball Illusion Technology(BIT). Link, a boy, went there to get some balls, but suddenly, he found that there were too many ways to get balls.

There are $2n$ buckets in the factory. Link may get $kx$ balls from the $2x-1^{th}$ bucket, where $k$ is a non-negtive integer. He may also get at most $x$ balls from the $2x^{th}$ bucket.

Link wanted to get $m$ balls, and he wondered how many ways there were to take out exactly $m$ balls. While Link is calculating the answer, he wants you to calculate it as well, and you should output the answer modulo $10^9+7$.
 

Input
The input consists of multiple test cases.

The first line contains an integer $T$ ($1 \leq T \leq 10^5$) -- the number of test cases.

Each test case contains two integers $n$ and $m$($1 \leq n,m \leq 10^6$).
 

Output
For each test case, print the answer modulo $10^9+7$ in a single line.
 

Sample Input
4 1 1 2 2 3 3 1000000 1000000
 

Sample Output
2 6 20 192151600
 

Source
 

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