N,D,K=map(int,input().split())
K-=N
D-=1
DP=[[0]*(K+1) for i in range(N+1)]
DP[0][0]=1
mod=10**9+7
def f(x,y):
  global DP
  if y<0:
    return 0
  else:
    return DP[x][y]

for i in range(N):
  for j in range(K+1):
    DP[i+1][j]=(f(i+1,j-1)+DP[i][j]-f(i,j-1-D))%mod
print(DP[N][K])