N, K, D = map(int, input().split())

def solve(N, K, D):
    if N == K:
        return N
    mod = 10**9 + 7
    x = ((N - K - 1) // (K - 1)) + 1
    f = N - (K - 1) * x        
    if D == 1:
        return f
    if f == 1:
        return pow(D, x, mod)
    dp = [1] * (x + 1)
    for _ in range(2, f):
        for idx in range(1, x + 1):
            dp[idx] += dp[idx - 1]
            dp[idx] %= mod
    cum = 0
    p = 1
    for a in range(0, x + 1):
        cum += p * dp[x - a]
        cum %= mod
        p *= D
        p %= mod
    return (cum * f) % mod

print(solve(N, K, D))