You and your friend are trapped in a space prison on an alien planet. The alien warden decides to give you and your friend a chance at freedom. He states that your friend shall be allowed to temporarily leave your cell and try to escape through an electric gate guarded by a 3-number passcode. If your friend answers incorrectly or says anything but the final answer, your friend will be thrown back in the prison. A computer will then tell your friend 4 clues if requested. If this passcode is properly answered, you and your friend shall be freed. You are then blindfolded and your friend leaves. You hear your friend walk down one of the numbered hallways to the gate. Your friend asks for the first clue. A voice answers, 'The numbers are in ascending order so that the number is greater than or equal to the number before it.' Your friend asks for the second clue. The voice says, 'The product of the 3 numbers is 36.' Your friend asks for the third clue. The voice says, 'The sum of the numbers is the number of the hallway you entered.' Your friend pauses for a moment and thinks. Your friend then asks for the fourth and final clue. The voice says, 'The largest number only appears once in the code.' You hear a beep. You hear your cell door swing open. You are free! What was the code?