N,D,K = map(int,input().split())
K -= N
MOD = 10**9+7

dp = [0] * (K+1)
dp[0] = 1
for _ in range(N):
    cums = [0]
    for a in dp:
        cums.append(cums[-1] + a)
    dp2 = []
    for i in range(K+1):
        dp2.append((cums[i+1] - cums[max(0,i+1-D)]) % MOD)
    dp = dp2
print(dp[-1])