mod = 10**9+7
n,d,k = map(int,input().split())
dp = [[0 for _ in range(k+1)] for _ in range(n+1)]
dp[0][0] = 1
for i in range(n):
    for j in range(k+1):
        end = min(j+d,k)
        end -= j
        for p in range(end+1):
            dp[i+1][j+p] += dp[i][j]+1
            dp[i+1][j+p] %= mod
ans = dp[-1][-1]
print(ans)