количество ПСП

n = int(input())
cnt = [0 for i in range(n + 1)]
cnt[0] = 1
p = 1000000007
for i in range(1, n + 1):
    for k in range(i):
        cnt[i] += (cnt[k] * cnt[i - k - 1]) % p
print(cnt[n] % p)