
    In a delivery fleet's hexagonal zone-based routing system, calculate the total number of delivery points that can be serviced when expanding from the central hub to the nth zone level, where each zone forms a hexagonal ring around the previous zone. The number of serviceable points follows the hexagonal number sequence, helping planners determine coverage capacity for each expansion level.
    

    
def hexagonal_num(n):
    """
    In a delivery fleet's hexagonal zone-based routing system, calculate the total number of delivery points that can be serviced when expanding from the central hub to the nth zone level, where each zone forms a hexagonal ring around the previous zone. The number of serviceable points follows the hexagonal number sequence, helping planners determine coverage capacity for each expansion level.
    

    """
def hexagonal_num(n):
    """
    In a delivery fleet's hexagonal zone-based routing system, calculate the total number of delivery points that can be serviced when expanding from the central hub to the nth zone level, where each zone forms a hexagonal ring around the previous zone. The number of serviceable points follows the hexagonal number sequence, helping planners determine coverage capacity for each expansion level.
    

    """
    return n * (2 * n - 1)