Message #2453

From: Eduard Baumann <baumann@mcnet.ch>
Subject: Re: [MC4D] MagicTile Solving
Date: Sat, 03 Nov 2012 00:35:12 +0100

30b was not a warming up. I did chose it by chance. I’m glad that 30a is simpler.
Regards
Ed

—– Original Message —–
From: Melinda Green
To: 4D_Cubing@yahoogroups.com
Sent: Friday, November 02, 2012 11:52 PM
Subject: Re: [MC4D] MagicTile Solving

Ah, I missed the ‘6’, thank you for the correction. This is one of the 3 IRPs that are as perfectly symmetric as the Platonic solids in every way. It is also the IRP twin of the original Rubik’s cube. I would still like to know why Nan’s solution is so much shorter.

I also do not understand why you see the IRP 4-5 b30 f001 as a warm-up exercise to the IRP {4,5} a30 F 0:0:1. True they both have 30 colors and genus 4, but they have different symmetries which I would guess would make the ‘a’ puzzle the simpler of the two.

-Melinda

On 11/2/2012 2:05 PM, Eduard Baumann wrote:

Wait.

The similar puzzle I mentioned is <br>
NOT<br>
MT irp &#123;4,5&#125; a30 F 0&#58;0&#58;1<br>
BUT<br>
MT irp &#123;4,6&#125; 12 F 0&#58;0&#58;1

I will attack <br>
MT irp &#123;4,5&#125; a30 F 0&#58;0&#58;1<br>
next time but I wanted study before he color topology of a30 and b30.

Ed

  ----- Original Message ----- <br>
  From&#58; Melinda Green <br>
  To&#58; 4D&#95;Cubing@yahoogroups.com <br>
  Sent&#58; Friday, November 02, 2012 9&#58;53 PM<br>
  Subject&#58; Re&#58; &#91;MC4D&#93; MagicTile Solving

{4,5} a30 is one of my favorite IRPs. I find it to be quite beautiful and symmetric. It is the one that I showcase on the main geometry page to introduce the subject. (Third image down.) The ‘b’ puzzle that surprised you is less symmetric but is still a fascinating structure. It looks very much like an apartment complex. I would like to know why Nan was able to solve it with such a smaller number of twists. Unless your macros are extremely long, it doesn’t seem like that can be the only difference. What do you think, Nan?

-Melinda

On 11/2/2012 11:17 AM, Eduard wrote:

Solving of MT irp {4,5} b30 F 0:0:1 —– || 11/02/2012 || 2393

Remark:
Over 2000 twists. I worked without macros this time. Not low hanging fruit. Here 30 colors. In the similar puzzle "irp 4-6 12 f001" with 12 colors I worked with macros and needed 21’000 twists (Nan only 400 !!).