
    Design a medical risk assessment algorithm that calculates a patient's cumulative health risk score based on weighted historical factors. Starting with the total number of risk factors, the algorithm should evaluate factors in pairs, with each pair having diminishing influence on the final score. The calculation begins with all factors considered and progressively reduces the weight by removing two factors at a time until no significant factors remain. The assessment should sum these weighted combinations, where each step considers (total factors - 2*current pair number) to reflect the decreasing importance of less critical factors. This weighted summation approach ensures that primary risk factors carry more weight in the final risk assessment score than secondary or tertiary factors.
    

    
def sum_series(n):
    """
    Design a medical risk assessment algorithm that calculates a patient's cumulative health risk score based on weighted historical factors. Starting with the total number of risk factors, the algorithm should evaluate factors in pairs, with each pair having diminishing influence on the final score. The calculation begins with all factors considered and progressively reduces the weight by removing two factors at a time until no significant factors remain. The assessment should sum these weighted combinations, where each step considers (total factors - 2*current pair number) to reflect the decreasing importance of less critical factors. This weighted summation approach ensures that primary risk factors carry more weight in the final risk assessment score than secondary or tertiary factors.
    

    """
def sum_series(n):
    """
    Design a medical risk assessment algorithm that calculates a patient's cumulative health risk score based on weighted historical factors. Starting with the total number of risk factors, the algorithm should evaluate factors in pairs, with each pair having diminishing influence on the final score. The calculation begins with all factors considered and progressively reduces the weight by removing two factors at a time until no significant factors remain. The assessment should sum these weighted combinations, where each step considers (total factors - 2*current pair number) to reflect the decreasing importance of less critical factors. This weighted summation approach ensures that primary risk factors carry more weight in the final risk assessment score than secondary or tertiary factors.
    

    """
    if n < 1:
        return 0
    else:
        return n + sum_series(n - 2)