N = int(input())
from itertools import permutations,accumulate
from functools import reduce

def popcnt(x):
    return bin(x)[2:].count('1')

ans = 0
for i in range(1<<(2*N)):
    if popcnt(i) != N:
        continue
    
    cnd = []
    for j in range(2*N):
        if (i>>j)&1:
            cnd.append(1)
        else:
            cnd.append(-1)
            
    if min(accumulate(cnd)) == 0:
        ans += 1
print(ans)