Message #1966

From: schuma <mananself@gmail.com>
Subject: Re: IRP {4,6} VT solved
Date: Wed, 14 Dec 2011 08:33:41 -0000

Thank you Andrey. When I first looked at this puzzle I thought it was too complicated and thus skipped it for other puzzles. After reading your post I revisited it and solved it. It is an interesting puzzle indeed. I managed to get the move count down to 382. But I’m sure the solution can be made more efficient.

Nan

— In 4D_Cubing@yahoogroups.com, "Andrey" <andreyastrelin@…> wrote:
>
> Hi all,
> today I tried to solve {4,6} (12 colors, vertex-turning) in IRP mode. It was hard enough. One twist touches about 1/3 of puzzle pieces (almost as in 3^3), and at the first glance, two intersecting circles have two areas of intersection. But some investigation revealed that actually number of elements in this puzzle is not 92 (as expected), but only 50: all non-vertex pieces are grouped in rigid pairs of elements symmetric with respect to any vertex (in surface geometry). For example, what we see as central grey central element is actually a half of grey-light_blue 2C piece. Edge elements are actually 4C, and petal elements are also grouped in pairs - but again, grey color is grouped only with light blue. So we can swap these elements… but not every pair of them - there are two orbits of petal stickers. I noticed it too late and spent some time trying to find setup moves that are actually impossible.
> Result is 517 twists. It was only 25-twist scramble, but I didn’t see any shortcuts, so it was like full-scrambled for me.
>
> Andrey
>