
'''simple docstring'''




from math import factorial







def 		lowerCAmelCase_				(   snake_case__ = 20						):




    '''simple docstring'''



    A       :   Optional[Any]					=						2 * n  # middle entry of odd rows starting at row 3 is the solution for n = 1,
    # 2, 3,...
    A       :   List[str]					=						n // 2

    return int(factorial(snake_case__						) / (factorial(snake_case__						) * factorial(n - k						))						)


if __name__ == "__main__":
      import sys

      if len(sys.argv) == 1:
            print(solution(20))
      else:
            try:
                  lowercase			:				List[str]    		=			int(sys.argv[1])
                  print(solution(n))
            except ValueError:
                  print('Invalid entry - please enter a number.')






"""simple docstring"""





def 						_lowerCAmelCase				(				UpperCamelCase_ = 10**9				):
		__SCREAMING_SNAKE_CASE            = 1
		__SCREAMING_SNAKE_CASE            = 2

		__SCREAMING_SNAKE_CASE            = 0
		__SCREAMING_SNAKE_CASE            = 0
		__SCREAMING_SNAKE_CASE            = 0
		while perimeter <= max_perimeter:
				perimeters_sum += perimeter

				prev_value += 2 * value
				value += prev_value

				__SCREAMING_SNAKE_CASE            = 2 * value + 2 if i % 2 == 0 else 2 * value - 2
				i += 1

		return perimeters_sum


if __name__ == "__main__":
							print(F"""{solution() = }""")




