
    Write a function that determines how many possible content moderation patterns exist where the sum of risk scores from n text indicators exactly matches the sum of risk scores from n image indicators, with each indicator being either safe (0) or flagged (1). The total pattern length is 2n, representing a complete content analysis sequence combining both text and image risk assessments.
    

    
def count_binary_seq(n):
    """
    Write a function that determines how many possible content moderation patterns exist where the sum of risk scores from n text indicators exactly matches the sum of risk scores from n image indicators, with each indicator being either safe (0) or flagged (1). The total pattern length is 2n, representing a complete content analysis sequence combining both text and image risk assessments.
    

    """
def count_binary_seq(n):
    """
    Write a function that determines how many possible content moderation patterns exist where the sum of risk scores from n text indicators exactly matches the sum of risk scores from n image indicators, with each indicator being either safe (0) or flagged (1). The total pattern length is 2n, representing a complete content analysis sequence combining both text and image risk assessments.
    

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