def count_binary_seq(n):
	 
	nCr = 1
	res = 1
	for r in range(1, n + 1): 
		nCr = (nCr * (n + 1 - r)) / r 
		res += nCr * nCr 
	return res 
def count_binary_seq(n):
    r2 = 1
    res = 1
   
    for r in range(1, n + 1):
        r2 = (r2 * (n + 1 - r)) / r
        res += r2 * r2
    return res