
    Given a patient's risk assessment level n, calculate the total number of possible risk factor combinations that need to be evaluated, where each level combines with all previous levels' factors in a cumulative pattern to form increasingly complex risk profiles. The number of combinations follows a tetrahedral progression, where each new level adds combinations with all previously considered risk factors.
    

    
def tetrahedral_number(n):
    """
    Given a patient's risk assessment level n, calculate the total number of possible risk factor combinations that need to be evaluated, where each level combines with all previous levels' factors in a cumulative pattern to form increasingly complex risk profiles. The number of combinations follows a tetrahedral progression, where each new level adds combinations with all previously considered risk factors.
    

    """
def tetrahedral_number(n):
    """
    Given a patient's risk assessment level n, calculate the total number of possible risk factor combinations that need to be evaluated, where each level combines with all previous levels' factors in a cumulative pattern to form increasingly complex risk profiles. The number of combinations follows a tetrahedral progression, where each new level adds combinations with all previously considered risk factors.
    

    """
    return n * (n + 1) * (n + 2) / 6