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Rikka with graph

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 243    Accepted Submission(s): 18


Problem Description
As we know, Rikka is poor at math. Yuta is worrying about this situation, so he gives Rikka some math tasks to practice. There is one of them:


A non-directed graph $G$ has no multiple edges and self loops. If every connected component of G has an EulerĄ¯s circuit, we call G perfect. Now Yuta wants to know the numbers of different perfect graphs which has $n$ vertices and no less than $m$ edges (In this problem, we think all the $n$ vertices are different from each other)


It is too difficult for Rikka. Can you help her?
 

Input
This problem has multi test cases (no more than $100$). For each test case, The first line contains two numbers $n,m(1 \leq n \leq 10^{18}, 0 \leq m \leq 80)$.
 

Output
For each test cases print only one number ¨C the answer. The answer may be very large, so you only print is module $1e9+7$.
 

Sample Input
3 0 4 0
 

Sample Output
2 8
 

Hint
For the first case, there are two possible ways. First one is that there is no edge in the graph.
Second one is that there is a edge between every two distinct vertices.
 

Source
 

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