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WANTED: New Dedge Flip Algorithm!

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Does anyone know what the briefest algorithm known to man is for the diagonal winged edge swap (pure form) in BQTM? (See sketch below).

I just need to know how many BQTM it is, not the algorithm itself or any other move measurements...

Why are you asking this here anyway? This edge swap is 1/2 of a PLL parity fix, and is just a NO-OP for fixing OLL (dedge flip) parity. Since the dedges need to stay together, the other edge pieces in your diagram will also have to swap as well. This amounts to two (an EVEN#) of 2-cycles, which will not change the OLL edge parity at all.

This thread is seeking some NEW and better ways to bring edge parity (OLL dedge flip) back to even. If you want to be helpful, please find some algs that are ODD#'s of even-cycles of edge pieces (that also keep the dedges paired). The pure parity alg is only one way of doing this, and does in fact fit the criterion for this problem, since it IS an odd#(1) of a 2-cycle of edge pieces. The problem with the pure parity alg, is that it has the most constraints (requiring all pieces to be placed exactly), and is therefore the most difficult to achieve. Finding OTHER algs that perform and odd# of even-cycles of edge pieces(while keeping the dedges paired, but not necessarily restoring everything else),will make for some NEW approaches to solving edge parity(OLL,dedge flip). Can you find some of these NEW algs?

reThinker
 

PHPJaguar

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UPDATE:
As a holiday special offer, I will now actually sell anyone the 19 outer block turn algorithm for the price of $1. That's right, for only $1 (and agreeing not to redistribute) you get to see the world's shortest known alg for OLL parity on 4x4x4. What a deal!

And of course, the 21q is still included! What are you waiting for?

Trade for any hand-found 23q pure OLL parity algorithms also accepted.
Pay'd.
 

Christopher Mowla

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Ok reThinker, I have found an algorithm which I believe is close to your description.

If the first portion of the alg is only performed, then one has an almost solved 3X3X3 form. If you do the last 2 half turn moves (which I added on to do the dirty work of restoration), then the cube matches your description much more: everything on the cube is preserved except for 6 composite edges. All 5 composite edges', other than the edge being "flipped" itself, orientation will be preserved (all corners are preserved too). With just a few more moves than that, this alg can become a pure double parity alg.


Total Moves:


Without final touches: 23 BQTM, 15 BHTM
With final touches: 27 BQTM, 17 BHTM

[main portion]
x r U2 r U2 r2 U2 r F2 x' l U2 l' U2 r' U2 r
[restoration]
B2 D2


Note: the algorithm can be executed using either single slice turns about l and r, or double layer turns, but I don't recommend using single slices because you will need to do 3 more half turn moves to restore the cube.

In summary:
27 BQTM, 17 BHTM
x r U2 r U2 r2 U2 r F2 x' l U2 l' U2 r' U2 r B2 D2

That's probably the best algorithm (for speed anyway) that I will be able to come up with that is very close to your request.
 
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Christopher Mowla

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The algorithm is a very clean, easy-to-execute alg that is very close to your description.
Not as clean and not as short as the well-known algorithms. You're going the wrong direction.
Well, if you ignore the last 2 half turn moves, it is a 23q. And, on the 4X4X4 and all other even cubes (by which all complimentary slices are turned).
 
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Stefan

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Well, if you ignore the last 2 half turn moves, it is a 23q.
Similarly, several 19q have been posted.

And, on the 4X4X4 and all other even cubes (by which all complimentary slices are turned), this alg is solely an odd permutation fix (not double parity).
False.

As far as I know, 25q is the shortest non-pure (solely OLL) alg out there.
Poor memory?
http://www.speedsolving.com/forum/showthread.php?p=239862#post239862
 

Christopher Mowla

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And, on the 4X4X4 and all other even cubes (by which all complimentary slices are turned), this alg is solely an odd permutation fix (not double parity).
False.
What are you talking about???? It is not a double parity fix on the 4X4X4 or on even cubes!

As far as I know, 25q is the shortest non-pure (solely OLL) alg out there.
Poor memory?
http://www.speedsolving.com/forum/showthread.php?p=239862#post239862[/quote]
Those are double parity manipulations, man.

I said, "solely an odd permutation fix", not a double parity fix. If you perform the algorithm like I have it, this should be a problem.
 

Christopher Mowla

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And, on the 4X4X4 and all other even cubes (by which all complimentary slices are turned), this alg is solely an odd permutation fix (not double parity).
False.
What are you talking about???? It is not a double parity fix on the 4X4X4 or on even cubes (assuming that you turn all symmetrical slices).

As far as I know, 25q is the shortest non-pure (solely OLL) alg out there.
Poor memory?
http://www.speedsolving.com/forum/showthread.php?p=239862#post239862
Those are double parity manipulations, man.

I said, "solely an odd permutation fix", not a double parity fix. If you perform the algorithm like I have it, this should not be a problem.
 
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Lucas Garron

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cmowla, this is a 25q, 16b alg that does exactly the same as yours:

l' D2 l B2 r' U2 l F2 l' B2 D2 r' D2 r (F2 D2)

Without the last two moves, it's 21q, 14b. (Does that contradict you yet?)

However, I know an alg that does this all in even fewer moves, except it even fully preserves F2L when you're done.

I appreciate your effort, and that you're trying to do things by hand, but, plainly, you're failing.

P.S.: r U2 r U2 r U2 is not annoying. It's quite fast, compared to full regrips. It's the reason world record holders use my alg.
 

Christopher Mowla

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P.S.: r U2 r U2 r U2 is not annoying. It's quite fast, compared to full regrips. It's the reason world record holders use my alg.
I actually do not consider any of your "algs" your own. The computer computed it, all you did was set it up. Thus, it is not really your alg, but the computer's algorithm.

That's why I actually try to find algs by hand (and I have been very successful with pure algorithms so far, in beating the computers in moves), so that I can really claim that they are my algorithms. This is puzzle theory, is it not?

And I am not failing, the alg you posted (though 2 less moves than mine, is very poor to execute and I think reThinker would think of performing my alg much more than that one).
 
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masterofthebass

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P.S.: r U2 r U2 r U2 is not annoying. It's quite fast, compared to full regrips. It's the reason world record holders use my alg.
I actually do not consider any of your "algs" your own. The computer computed it, all you did was set it up. Thus, it is not really your alg, but the computer's algorithm.

That's why I have the nerve to actually try to find algs by hand, so that I can really claim that they are my algorithms.

And I am not failing, the alg you posted (though 2 less moves than mine, is very poor to execute and I think reThinker would think of performing my alg much more than that one).

personally, as a decent speedcuber, I can't stand a single one of "your" algorithms. I mean, I find absolutely none of them to be speedsolveable at all.

Also, I don't know what you are smoking because

x (Rr) U2 (Rr) U2 (Rr)2 U2 (Rr) F2 x' (Ll) U2 (Ll)' U2 (Rr)' U2 (Rr) B2 D2

is a double parity fix on any cube. Not only is it horrific to execute, but it requires a fix of the F2L as well, which is absolutely pointless for speedsolving.
 
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joey

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Lucas went to the trouble of finding them, wether he used a computer or not, I would still call them his; since he was the first to post them etc.

No-one really cares wether a computer is used or not, I think you need to get over that. I do find it impressive that you're not using a computer.. but I wont use them just becasue of that!

ps your alg is double parity.. I'm confused why you're saying it isn't.
 

Christopher Mowla

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ps your alg is double parity.. I'm confused why you're saying it isn't.
Just look at the picture of the 4X4X4 I posted. There are 4 composite edges (besides the flipped edge) that are affected. Those 4 can be solved back with a 3X3X3 algorithm, not a 2 2cycle exchange of individual winged edge pieces. That's why. On the 5X5X5 (and all other odd cubes), it is double parity, but not on the 4X4X4 on bigger even cubes which you treat like a 4X4X4.
 
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masterofthebass

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ps your alg is double parity.. I'm confused why you're saying it isn't.
Just look at the pictures I posted. There are 4 composite edges (besides the flipped edge) that are affected. Those 4 can be solved back with a 3X3X3 algorithm, not a 2 2cycle exchange of individual winged edge pieces. That's why.
But you are ignoring the fact that your algorithm switches 2 corners as well, which leaves a PLL parity situation for speedsolving. Also, for speedsolving purposes, you should add the 12 QTM that it would take to fix the f2l that you messed up, making your total algorithm for double parity 39 BQTM.
 

Christopher Mowla

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x (Rr) U2 (Rr) U2 (Rr)2 U2 (Rr) F2 x' (Ll) U2 (Ll)' U2 (Rr)' U2 (Rr) B2 D2

is a double parity fix on any cube. Not only is it horrific to execute, but it requires a fix of the F2L as well, which is absolutely pointless for speedsolving.
Have you not read the very description of this thread? I wrote this alg to do this on purpose. reThinker specially said that one F2L slot should be open for distortion.

What dan said basically ^^
I'm not saying give up.. I'm just saying this alg isn't probably going to be used for 4x4 speedsolving.
I know. I didn't really claim that it was the best. The reason I posted this alg was mainly for reThinker because he asked me to try my best to find an algorithm that matched his description. That's all. I personally like my pure algs much better than this one, too.
 
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