import java.util.Scanner;

public class Main
{
    public static void main(String [] args)
    {
        Scanner key = new Scanner(System.in);
        int num = key.nextInt();
        long sum = 0;
        for(int i=0; i<=num; i++)
        {
            
            if(i % 3 == 0 || i % 5 == 0)
                continue;
            else
            {
                sum = sum + i;
            }
                
            
        }
        System.out.println(sum);
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz