from itertools import accumulate

N, d, K = map(int, input().split())
mod = 10**9+7

dp = [[0]*(K+2) for _ in range(N+1)]
dp[0][0] = 1
for i in range(1, N+1):
    for j in range(K+1):
        if dp[i-1][j] > 0 and j+1<=K:
            dp[i][j+1] += dp[i-1][j]
            dp[i][min(j+d+1, K+1)] -= dp[i-1][j]
    for k in range(1,K+1):
        dp[i][k] += dp[i][k-1]
        dp[i][k] %= mod
print(dp[-1][-2])