
    Write a function to determine the number of possible emergency room patient influx patterns over a 2n-hour period, where the total number of peak hours in the first n hours equals the total number of peak hours in the last n hours. Each hour can only be classified as either peak (1) or normal (0) occupancy.
    

    
def count_binary_seq(n):
    """
    Write a function to determine the number of possible emergency room patient influx patterns over a 2n-hour period, where the total number of peak hours in the first n hours equals the total number of peak hours in the last n hours. Each hour can only be classified as either peak (1) or normal (0) occupancy.
    

    """
def count_binary_seq(n):
    """
    Write a function to determine the number of possible emergency room patient influx patterns over a 2n-hour period, where the total number of peak hours in the first n hours equals the total number of peak hours in the last n hours. Each hour can only be classified as either peak (1) or normal (0) occupancy.
    

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