def Pn(b, n):
  if n<= 0:
    return 0

  ans = b
  for i in range(1, b):
    ans *= b+i
  for i in range(1, b):
    ans /= i+1
  return ans

def solve():
  S = raw_input()
  S = [int(s) for s in S.split()]
  N = S[0]
  K = S[1]
  print(Pn(K, N-2*K+2))

T = int(raw_input())
for i in range(0, T):
  solve()