
    Given n distinct post-discharge behavioral factors monitored for a patient, determine the total number of possible ways these factors can be grouped into different risk categories for readmission assessment. Each factor must be assigned to exactly one risk category, and empty categories are not allowed in the grouping. The solution will help healthcare providers understand all possible risk pattern combinations for patient monitoring.
    

    
def bell_number(n):
    """
    Given n distinct post-discharge behavioral factors monitored for a patient, determine the total number of possible ways these factors can be grouped into different risk categories for readmission assessment. Each factor must be assigned to exactly one risk category, and empty categories are not allowed in the grouping. The solution will help healthcare providers understand all possible risk pattern combinations for patient monitoring.
    

    """
def bell_number(n):
    """
    Given n distinct post-discharge behavioral factors monitored for a patient, determine the total number of possible ways these factors can be grouped into different risk categories for readmission assessment. Each factor must be assigned to exactly one risk category, and empty categories are not allowed in the grouping. The solution will help healthcare providers understand all possible risk pattern combinations for patient monitoring.
    

    """
    bell = [[0 for i in range(n + 1)] for j in range(n + 1)]
    bell[0][0] = 1
    for i in range(1, n + 1):
        bell[i][0] = bell[i - 1][i - 1]
        for j in range(1, i + 1):
            bell[i][j] = bell[i - 1][j - 1] + bell[i][j - 1]
    return bell[n][0]