Re: [Computer-go] Paper “Complexity of Go” by Robson
A last esthetic suggestion: let's mark the lower group and label with 1 the last move Black did in the ko: https://drive.google.com/file/d/1L62m7i_IJX8FCB_8rIOwjYK3tR1GZZaq/view?usp=sharing On 23 June 2018 at 00:19, Marcel Crasmaru wrote: > Well all my reasoning was good but for the formula which is actually > > F = z || (y && x) :-) > > Mea culpa I didn't see that the ladder choices are reversed. I let > other people try showing that the group is alive in John's initial > problem (last move was B capture at x, the lower side ko). > > --Marcel > > On 23 June 2018 at 00:06, Marcel Crasmaru wrote: >> OK I think there is one thing to be done to make the solution longer: >> >> 1. mark the middle ko and then >> 2. problem should be: B just captured in the middle ko and W is to >> move - is the group alive? >> >> See here: >> https://drive.google.com/file/d/1J5Xn4XkOqSsYx0AEBQJj6EL-SjNqNq-o/view?usp=sharing >> >> Assuming x is the top ko, y the middle one etc. the problem is then >> equivalent to >> F = z && (y || x) with (x = 1, y = 0, z = 0, F is false) and W cannot play >> at y. >> >> As F is false W has to take the ko at z (x = 1, y = 0, z = 1, F becomes true) >> B takes at x (x = 0, y = 0, z = 1 F is false) >> W takes at y (x = 0, y = 1, z = 1, F true), >> B takes at z (x = 0, y = 1, z = 0, F false) and W is dead as no matter >> what W does F remains false (equivalent to ladders failing for W). >> >> --Marcel >> >> On 22 June 2018 at 22:27, Marcel Crasmaru wrote: >>> Errata: assuming x is the top ko then the formula encoded by this problem is >>> >>> z && (y || x) >>> >>> with x = 1, y = 0, z = 0 and W cannot play at z. Thus W is already >>> dead you cannot make the formula true. >>> >>> --Marcel >>> >>> On 22 June 2018 at 22:19, Marcel Crasmaru wrote: The position looks OK is great - I didn't find any side solutions. Just one observation: I think this encodes x && y || y || z and W is dead already thus is arguably a easier problem :) Should make for a great wall poster. On 22 June 2018 at 19:48, John Tromp wrote: > at the bottom of my Go page http://tromp.github.io/go.html, which also > contains an sgf link. > Direct link to image: http://tromp.github.io/img/WO5lives.png > > Enlarging the board to 29x29 allows for a much better final (I hope) > look, close to my first attempt. > > -John > ___ > Computer-go mailing list > Computer-go@computer-go.org > http://computer-go.org/mailman/listinfo/computer-go ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Paper “Complexity of Go” by Robson
Well all my reasoning was good but for the formula which is actually F = z || (y && x) :-) Mea culpa I didn't see that the ladder choices are reversed. I let other people try showing that the group is alive in John's initial problem (last move was B capture at x, the lower side ko). --Marcel On 23 June 2018 at 00:06, Marcel Crasmaru wrote: > OK I think there is one thing to be done to make the solution longer: > > 1. mark the middle ko and then > 2. problem should be: B just captured in the middle ko and W is to > move - is the group alive? > > See here: > https://drive.google.com/file/d/1J5Xn4XkOqSsYx0AEBQJj6EL-SjNqNq-o/view?usp=sharing > > Assuming x is the top ko, y the middle one etc. the problem is then > equivalent to > F = z && (y || x) with (x = 1, y = 0, z = 0, F is false) and W cannot play at > y. > > As F is false W has to take the ko at z (x = 1, y = 0, z = 1, F becomes true) > B takes at x (x = 0, y = 0, z = 1 F is false) > W takes at y (x = 0, y = 1, z = 1, F true), > B takes at z (x = 0, y = 1, z = 0, F false) and W is dead as no matter > what W does F remains false (equivalent to ladders failing for W). > > --Marcel > > On 22 June 2018 at 22:27, Marcel Crasmaru wrote: >> Errata: assuming x is the top ko then the formula encoded by this problem is >> >> z && (y || x) >> >> with x = 1, y = 0, z = 0 and W cannot play at z. Thus W is already >> dead you cannot make the formula true. >> >> --Marcel >> >> On 22 June 2018 at 22:19, Marcel Crasmaru wrote: >>> The position looks OK is great - I didn't find any side solutions. >>> Just one observation: I think this encodes x && y || y || z and W is >>> dead already thus is arguably a easier problem :) >>> >>> Should make for a great wall poster. >>> >>> On 22 June 2018 at 19:48, John Tromp wrote: at the bottom of my Go page http://tromp.github.io/go.html, which also contains an sgf link. Direct link to image: http://tromp.github.io/img/WO5lives.png Enlarging the board to 29x29 allows for a much better final (I hope) look, close to my first attempt. -John ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Paper “Complexity of Go” by Robson
OK I think there is one thing to be done to make the solution longer: 1. mark the middle ko and then 2. problem should be: B just captured in the middle ko and W is to move - is the group alive? See here: https://drive.google.com/file/d/1J5Xn4XkOqSsYx0AEBQJj6EL-SjNqNq-o/view?usp=sharing Assuming x is the top ko, y the middle one etc. the problem is then equivalent to F = z && (y || x) with (x = 1, y = 0, z = 0, F is false) and W cannot play at y. As F is false W has to take the ko at z (x = 1, y = 0, z = 1, F becomes true) B takes at x (x = 0, y = 0, z = 1 F is false) W takes at y (x = 0, y = 1, z = 1, F true), B takes at z (x = 0, y = 1, z = 0, F false) and W is dead as no matter what W does F remains false (equivalent to ladders failing for W). --Marcel On 22 June 2018 at 22:27, Marcel Crasmaru wrote: > Errata: assuming x is the top ko then the formula encoded by this problem is > > z && (y || x) > > with x = 1, y = 0, z = 0 and W cannot play at z. Thus W is already > dead you cannot make the formula true. > > --Marcel > > On 22 June 2018 at 22:19, Marcel Crasmaru wrote: >> The position looks OK is great - I didn't find any side solutions. >> Just one observation: I think this encodes x && y || y || z and W is >> dead already thus is arguably a easier problem :) >> >> Should make for a great wall poster. >> >> On 22 June 2018 at 19:48, John Tromp wrote: >>> at the bottom of my Go page http://tromp.github.io/go.html, which also >>> contains an sgf link. >>> Direct link to image: http://tromp.github.io/img/WO5lives.png >>> >>> Enlarging the board to 29x29 allows for a much better final (I hope) >>> look, close to my first attempt. >>> >>> -John >>> ___ >>> Computer-go mailing list >>> Computer-go@computer-go.org >>> http://computer-go.org/mailman/listinfo/computer-go ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Paper “Complexity of Go” by Robson
Errata: assuming x is the top ko then the formula encoded by this problem is z && (y || x) with x = 1, y = 0, z = 0 and W cannot play at z. Thus W is already dead you cannot make the formula true. --Marcel On 22 June 2018 at 22:19, Marcel Crasmaru wrote: > The position looks OK is great - I didn't find any side solutions. > Just one observation: I think this encodes x && y || y || z and W is > dead already thus is arguably a easier problem :) > > Should make for a great wall poster. > > On 22 June 2018 at 19:48, John Tromp wrote: >> at the bottom of my Go page http://tromp.github.io/go.html, which also >> contains an sgf link. >> Direct link to image: http://tromp.github.io/img/WO5lives.png >> >> Enlarging the board to 29x29 allows for a much better final (I hope) >> look, close to my first attempt. >> >> -John >> ___ >> Computer-go mailing list >> Computer-go@computer-go.org >> http://computer-go.org/mailman/listinfo/computer-go ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Paper “Complexity of Go” by Robson
The position looks OK is great - I didn't find any side solutions. Just one observation: I think this encodes x && y || y || z and W is dead already thus is arguably a easier problem :) Should make for a great wall poster. On 22 June 2018 at 19:48, John Tromp wrote: > at the bottom of my Go page http://tromp.github.io/go.html, which also > contains an sgf link. > Direct link to image: http://tromp.github.io/img/WO5lives.png > > Enlarging the board to 29x29 allows for a much better final (I hope) > look, close to my first attempt. > > -John > ___ > Computer-go mailing list > Computer-go@computer-go.org > http://computer-go.org/mailman/listinfo/computer-go ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Paper “Complexity of Go” by Robson
at the bottom of my Go page http://tromp.github.io/go.html, which also contains an sgf link. Direct link to image: http://tromp.github.io/img/WO5lives.png Enlarging the board to 29x29 allows for a much better final (I hope) look, close to my first attempt. -John ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] thumbs crossed ?! [offtopic]
On 2018-06-22 at 09:07, "Ingo Althöfer" <3-hirn-ver...@gmx.de> wrote with subject “[Computer-go] thumbs crossed ?! [offtopic]”: >>> I think you meant "cross my fingers". > > yes that is the American way to formulate is. > Our Chancellor, however, prefers "thumbs pressed". Not only Mrs. Merkel, that’s simply the way we say it in Germany ;-) (But Ingo knows this, of course) Cordially, Tom -- Thomas Rohde Wiesenkamp 12, 29646 Bispingen, GERMANY -- t...@bonobo.com ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Paper “Complexity of Go” by Robson
> The hunt for the simplest possible ko gadget continues... Latest attempt at the usual place: >>> at the bottom of my Go page http://tromp.github.io/go.html, which also >>> contains an sgf link. >>> Direct link to image: http://tromp.github.io/img/WO5lives.png Unfortunately not as pretty as the previous arrow. But let's get it correct before getting it pretty... ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Paper “Complexity of Go” by Robson
> Hopefully fixed now. Nope. Still no good. White can play O13, M11, or Q11 instead of recapturing ko. The hunt for the simplest possible ko gadget continues... ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Paper “Complexity of Go” by Robson
Hello, I assume after white plays at U22, black T20, white T19, black should have a choice of playing either at S21, capturing one white stone and leading the ladder to the top ko, or at S20, leading the ladder to the middle ko. However, if black plays at S21, the sequence: wS20 bT21 wR20 bS22 wS23 bR22 wQ22 bR23 wR24 Results in a win for white, regardless of who is holding the top ko. 2018-06-22 0:27 UTC+02:00, John Tromp : Direct link to image: http://tromp.github.io/img/WO5lives.png > > Might be useful for go event organizers in need of arrow signs... > > regards, > -John > ___ > Computer-go mailing list > Computer-go@computer-go.org > http://computer-go.org/mailman/listinfo/computer-go ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Paper “Complexity of Go” by Robson
Hello, I assume after white pla 2018-06-22 0:27 UTC+02:00, John Tromp : Direct link to image: http://tromp.github.io/img/WO5lives.png > > Might be useful for go event organizers in need of arrow signs... > > regards, > -John > ___ > Computer-go mailing list > Computer-go@computer-go.org > http://computer-go.org/mailman/listinfo/computer-go ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Paper “Complexity of Go” by Robson
> I also think that what makes real go that hard is ko, but you've shown that > it's > equivalent to ladder, which frankly baffles me. I'd love to understand that. Just different definitions of "hard"? Ko is still way harder (more confusing, harder to discover a winning move when one exists) than ladders in the way they each appear in typical games. > http://tromp.github.io/img/WO5lives.png > > Might be useful for go event organizers in need of arrow signs... :-) ...though it might end up with blocked corridors, as people stand around the signs and argue about the best move, instead of going where the organizers want them to go! Darren ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
[Computer-go] thumbs crossed ?! [offtopic]
Hi Richard, >> I think you meant "cross my fingers". yes that is the American way to formulate is. Our Chancellor, however, prefers "thumbs pressed". Look here: https://www.bz-berlin.de/data/uploads/2014/07/merkel_1404473813-768x432.jpg In the photo, look at the single white Go stone and the single dark Go stone. Angela Merkel is a master of Aji Keshi (my opinion). Ingo. ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
