5779：Tower Defence

Little White recently likes playing Tower Defence. She wants to make a map. The map is an undirected graph which has n vertices(graph may not connect).The length of each edge is 1.The shortest distance of vertice 1 to any other vertices is not equal to k.She wants to know how many graphs which satisfy all these conditions.If two vertices is disconnected, the distance between them is infinite.

The first line of input is an integer T（$1\leq T\leq 10$)
For each test case the first line contains two integers n and k($1\leq k$，$n\leq 60$)

For each testcase , output a line, the answer mod 1，000，000，007