func lagarias n . if n < 0 return -lagarias -n . if n = 0 or n = 1 return 0 . f = 2 while n mod f <> 0 f += 1 . q = n / f if q = 1 return 1 . return q * lagarias f + f * lagarias q . for n = -99 to 100 write lagarias n & " " .