# INPUT NUMBER OF EVEN NUMBERS
def print_error_messages(): #function to print error message if user enters a negative number
  print("Invalid number, please enter a Non-negative number!")
  exit()


try:
  n=int(input('Amount: ')) #user input
except ValueError:
  print_error_messages()

start=0

if n < 0:
  print_error_messages()

for i in range(n): #loop till the number n entered by the user
  if(n==0):
    print(start) #prints 0 first as it is an even number
    start+=2 #increases the value of start by 2 to get to the next even number
  else(n%2==0):
    print(start)