def popcnt3(n):
    c = (n & 0x5555555555555555) + ((n >> 1) & 0x5555555555555555)
    c = (c & 0x3333333333333333) + ((c >> 2) & 0x3333333333333333)
    c = (c & 0x0F0F0F0F0F0F0F0F) + ((c >> 4) & 0x0F0F0F0F0F0F0F0F)
    c = (c & 0x00FF00FF00FF00FF) + ((c >> 8) & 0x00FF00FF00FF00FF)
    c = (c & 0x0000FFFF0000FFFF) + ((c >> 16) & 0x0000FFFF0000FFFF)
    c = (c & 0x00000000FFFFFFFF) + ((c >> 32) & 0x00000000FFFFFFFF)
    return c


n = int(input())

a = 0
for i in range(1 << 2 * n):
    if not i & 1:
        continue
    if i >> 2 * n & 1:
        continue
    if popcnt3(i) != n:
        continue
    s = 0
    for j in range(2 * n):
        if i >> j & 1:
            s += 1
        else:
            s -= 1
        if s < 0:
            break
    if s == 0:
        a += 1

print(a)