from sys import stdin
def main():
    #入力
    readline=stdin.readline
    N,d,K=map(int,readline().split())
    dp=[[0]*(K+1) for _ in range(N+1)]
    dp[0][0]=1

    for i in range(1,N+1):
        for j in range(i,K+1):
            dp[i][j]+=dp[i-1][j-1]
            if 0<=j-d-1<=K:
                dp[i][j]-=dp[i-1][j-d-1]
        for j in range(i,K+1):
            dp[i][j]+=dp[i][j-1]
            dp[i][j]%=10**9+7

    print(dp[N][K])

if __name__=="__main__":
    main()