# Rubik’s 5x5x5 Cube Challenge

Ilya Lichman

The first four times we invited you to take on our game challenges, they all operated at the same level of difficulty for everyone — whether inverting the state of Conway's Life game, inventing ways to split a polymino, solving PLM anagrams, or composing a most beautiful fractal, given constraints.

With today’s challenge, you get to choose the level of difficulty. As the ideal — and the most accurate scale of difficulty known to man — we will use the skill levels from the Doom computer game (illustrated below), which incidentally is now 33 = 3*3*3 = 27 years old.

### Why Doom, and Why Now?

When we first planned this Rubik’s cube challenge at the beginning of August, the stars aligned in a remarkable way. Judge for yourself:

• Ernő Rubik turned 77 years old
• Doom was released by id Software 27 years ago
• John Carmack turned 50

When you add up the ages of one of the key figures to the success of id Software (Carmack) with one of his creations (Doom), we get the age of the creator of the Rubik's Cube! This is no coincidence — or is it?

### Alphabet On a Cube

Let's go straight to a big 5x5x5 Rubik’s cube. It has six sides, so there is enough room to fit the five letters of the name ‘LEDAS’, with one side to spare. The first two letters might look like this:

This leaves one side free on which we can add the LEDAS logo, illustrated below. As the resolution is just 5x5, the logo will suffer from severe pixelation and so may look non-ideal.

### Our Cube Challenge

The Doom game offers the following levels of difficulty:

Here is how we will apply the levels to the LEDAS logo challenge:

Level “I’m too young to die”: Build each of the 'L', 'E', 'D', 'A', and 'S' letters, one at a time, on a face of the cube. At this level, there is no need to arrive at two or more letters at the same time. In other words, build a cube with a letter 'L'. Then forget about 'L', and build another configuration with 'E', and so on.

Send us pictures of the faces of the cube that have a letter (or images from a simulator, such as at grubiks.com/puzzles/rubiks-professors-cube-5x5x5). It would be great if you could also send us the sequence of actions by which you arrived at the letter(s).

Level “Hey, not too rough”: Think about what would be theoretically achievable as an arrangement of the five letters on the faces of the cube. It may seem elementary, but if you count the number of cells of each color, it gets interesting.

Send us a drawing of your correct arrangement of the elements on Rubik's 5x5x5 cube on which you can read all five letters. It is OK if, at this level, you invent your own font :).

Level “Hurt me plenty”: Offer a constructive way to form a sequence of turns from the original state of the cube which arrives at the desired configuration – a configuration in which all five letters are visible.

Level “Ultra-violence”: You’re required to record everything you do with the cube, and then present a picture of a 5x5x5 cube, or the result of a simulation.

Level “Nightmare!”: The pinnacle of this competition’s madness is to not only build the five letters of the word LEDAS, but also on the remaining sixth face get a figure as similar to the LEDAS logo as possible.

Tip

For your experiments it can be useful to have several solved 5x5x5 Rubik's cubes, so you should either know how to quickly solve the cube yourself or ask for help from a volunteer. An alternative is to use the software simulator.

### The LEDAS Cube Contest

We invite readers to submit original solutions at the different skill levels. Send an email to quiz@ledas.com with your ideas, explanations, programs, and photos/screenshots. (If you don't want your name made public, then please say so in your submission.) We look forward to seeing what you can come up with!