It is currently Wed Aug 23, 2017 4:53 am

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 29 posts ]  Go to page Previous  1, 2
Author Message
Offline
 Post subject: Re: The most difficult problem ever. Igo Hatsuyoron 120
Post #21 Posted: Wed May 13, 2015 2:58 am 
Lives in gote
User avatar

Posts: 699
Liked others: 6
Was liked: 86
Rank: German 1 Kyu
Dear Robert,

Thank you very much for your interest. I will answer step by step, in several single posts, in order to ease citation.

+ + + + + + + + + + +

Some more general remarks first.


All our findings that have an effect on the problem's final score -- and so led to the refutation of the known professional solutions -- are explained in the 2011 book.

All other -- later -- findings can be valued to be somewhat "technical" only, these do not affect the outcome of the problem any more.


Therefore, if you are not interested in

-- the correct order of moves,
-- professional validation of our ideas,
-- correction of further professional mistakes (as are in Cheng Xiaoliu's 2010 book on "Igo Hatsuyoron"),
-- stunning professional Tesuji,
-- further "natural looking" alternate moves that are extremely difficult to refute (on amateur level),
-- further "natural looking" alternate moves that benefit their initiator in "normal" games, but not in this very special problem, and
-- further insights in other aspects of the problem,

you will be fine with our 2011 book.

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by three amateurs)

Top
 Profile  
 
Offline
 Post subject: Re: The most difficult problem ever. Igo Hatsuyoron 120
Post #22 Posted: Wed May 13, 2015 5:44 am 
Lives in gote
User avatar

Posts: 699
Liked others: 6
Was liked: 86
Rank: German 1 Kyu
How to begin with ?


As a matter of course, Volume I contains many more variations than our 2011 book. Its structure is nested, complex, and somewhat confused.

It was a lot of work to re-organise the order of variations -- that has grown historically over a long period of time -- so that (with only a very few exceptions) the result of a higher-level variation is always better (for its initiator) than the result of the corresponding lower-level ones.


You will find maps of this structure, which hopefully will help cloudlessness:

Image

These maps might be useful, especially if you ever find a mistake in one of our sub-variations that changes its outcome. You will be able to easily identify, whether there are implications on higher level variations.


There is the danger that you will find some of these sub-variations superfluous, or boring. However, it is very difficult for me to decide on the erasure of such a sub-variation. Due to the "cloudy", and complex, structure, it is not unlikely that there is a reference to just this sub-variation -- or any in its immediate surrounding.

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by three amateurs)


Last edited by Cassandra on Wed May 13, 2015 10:08 am, edited 1 time in total.
Top
 Profile  
 
Offline
 Post subject: Re: The most difficult problem ever. Igo Hatsuyoron 120
Post #23 Posted: Wed May 13, 2015 6:06 am 
Lives in gote
User avatar

Posts: 699
Liked others: 6
Was liked: 86
Rank: German 1 Kyu
The story of "Our Solution" is devided into three sections now:


-- The creation of the Hanezeki in the lower right corner, including the flight of the Hanezeki's Tail through the centre of the board (until shortly before its end).
-- The very decisive moment of the problem, with my Guzumi played in the upper right corner (no other move will win Black the problem).
-- The plain sailing rest of the solution sequence, wherein nothing decisive will happen any more (possibly with the exception of Yamada Shinji's Tsuke in the upper left corner).

Most voluminous is section 2, including a very extensive treatment of Joachim's Ko-Semeai (found in mid-2011). Section 2 also contains the discussion of an idea of Michael Redmond 9p, with respect to a Kikashi in the upper right corner (that "would 'naturally' come into a professional's mind", but does not really help in the problem).


Each section starts with "Technical Notes", i.e. a selection of technical aspects, which discussion we assessed to be too special for our general overview "A Summary of Our Solution" (slightly extended, compared to our 2011 book).

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by three amateurs)


Last edited by Cassandra on Wed May 13, 2015 6:37 am, edited 1 time in total.
Top
 Profile  
 
Offline
 Post subject: Re: The most difficult problem ever. Igo Hatsuyoron 120
Post #24 Posted: Wed May 13, 2015 6:29 am 
Lives in gote
User avatar

Posts: 699
Liked others: 6
Was liked: 86
Rank: German 1 Kyu
The correct order of moves

Prof. Jeong SooHyun 9p (from Myongji University), and Ōhashi Hirofumi 6p, kindly provided us with indications on the correct timing for starting the "endgame" of the problem (much earlier than in our 2011 book), and on the correct order of moves for filling the Nakade on the left side.

We also found that it is technically correct to play Harry's Hasami-Tsuke-sequence in the upper right corner before the Guzumi (and not the other way round, as in our 2011 book).



Professional validation of our ideas

Prof. Jeong SooHyun was so very kind to validate my idea of the "second Throw-in" in the Hanezeki (of which Fujisawa Hideyuki 9p originally said that it would be fatal). This move is also used by Cheng Xiaoliu 6p in his 2010 book.

Joachim's "late" Oki -- that put Fujisawa's originally solution into question -- is also used by Cheng now. Cheng gives the result of the problem as "Jigo" now, but he missed Yamada's Tsuke in the upper left corner, gaining two points for White.

Seen overall, Harry's Hasami-Tsuke-sequence is assessed to be a "natural" endgame sequence. However, its territorial effect (four points) is only valid in conjunction with my Guzumi; there is no effect with the "classical" line of play.

So far, no professional engaged found a flaw with my Guzumi.



Correction of further professional mistakes (as are in Cheng Xiaoliu's 2010 book on "Igo Hatsuyoron")

We discuss all the "new" variations, given by Cheng in his 2010 book (as compared with his first 1988 / 2003 book), also correcting some of his oversights.



Stunning professional Tesuji

Michael Redmond was so kind to provide us with some stunning Tesuji, when commenting White's strongest Tenuki-option after my Guzumi.

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by three amateurs)

Top
 Profile  
 
Offline
 Post subject: Re: The most difficult problem ever. Igo Hatsuyoron 120
Post #25 Posted: Wed May 13, 2015 6:35 am 
Lives in gote
User avatar

Posts: 699
Liked others: 6
Was liked: 86
Rank: German 1 Kyu
Volume II begins with the treatment of all the professional solutions that are known to us, including their sub-variations.

Herein, you will find all the (sub-) variations that are special to the professional line of play.


"The Evolution of Professionals' Knowledge" explains the historical professional path -- from Fujisawa to Cheng.

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by three amateurs)

Top
 Profile  
 
Offline
 Post subject: Re: The most difficult problem ever. Igo Hatsuyoron 120
Post #26 Posted: Wed May 13, 2015 6:53 am 
Lives in gote
User avatar

Posts: 699
Liked others: 6
Was liked: 86
Rank: German 1 Kyu
The second part of Volume II (= part 3 seen overall) discusses the "Evolution of Amateur's Knowledge".


In principle,

-- The History of the Problem's Final Score (1999 - 2011),
-- The Decisive Moment in the Historical Line of Play (2002 - 2007),
-- Guzumi at Top Right (2007 - 2009), and
-- Various Kikashi in the Hanezeki (2007 - 2011; 2014)

can also be found in our 2011 book.

In 2014, Harry revealed some very interesting aspects in one of the "classical" Hanezeki-problems (containg the well-known "basic" shape"), which we explain in detail.


Joachim's Ko-Semeai is not trivial at all.

We encountered massive difficulties in browsing through all the possible variations, in order to "prove" that this Ko-Semeai is no valid option for Black. As "usual" with Dosetsu's masterpiece, Black has one liberty too few to be successful and / or one Ko-threat too few.

Therefore, we tried some kind of "reverse engineering" -- starting with a later moment in these sequences -- for comparative studies in "Joachim's Ko-Semeai -- Putting the Cart Before the Horse (2013 - 2015)". This second, different approach helped us a lot to find mistakes in our earlier sequences.

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by three amateurs)

Top
 Profile  
 
Offline
 Post subject: Re: The most difficult problem ever. Igo Hatsuyoron 120
Post #27 Posted: Wed May 13, 2015 7:01 am 
Lives in gote
User avatar

Posts: 699
Liked others: 6
Was liked: 86
Rank: German 1 Kyu
The third part of Volume II (= part 4 seen overall) contains further topics.


Amoung the further structural elements of the problem,

-- About Approach-Move Liberties (2009)
-- About Hanezeki (2009; 2015)

can be also found in our 2011 book (in principle).
There is a supplement on Hanezeki, due to Harry's findings, mentioned above.


"About Ko in a Semeai Between Two One-Eyed Groups (2012)" was my first attempt to create a different approach on Joachim's Ko-Semeai, using simplified positions. However, there were some rumours that this chapter might be too mathematical orientated, thus I finally developed "Putting the cart before the horse".


"Igo Hatsuyōron 120 and Go Playing Programs (2009 - 2011)" explains my trials with Many Faces of Go during the investigations in White's Tenuki-variations after my Guzumi.

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by three amateurs)

Top
 Profile  
 
Offline
 Post subject: Re: The most difficult problem ever. Igo Hatsuyoron 120
Post #28 Posted: Wed May 13, 2015 7:09 am 
Lives in gote
User avatar

Posts: 699
Liked others: 6
Was liked: 86
Rank: German 1 Kyu
All the contents described above, which has been developed until mid-2013, can be found in our 300th Anniversary Edition "The most difficult problem ever: Igo Hatsuyōron 120" with SmartGo Books.

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by three amateurs)

Top
 Profile  
 
Offline
 Post subject: Re: The most difficult problem ever. Igo Hatsuyoron 120
Post #29 Posted: Sat Aug 05, 2017 12:29 am 
Lives in gote
User avatar

Posts: 699
Liked others: 6
Was liked: 86
Rank: German 1 Kyu
A few days ago, Harry Fearnley of our amateur research team found a mistake in our previous solution to Igo Hatsuyoron 120.

Harry revealed an AlphaGo-ish large trade on the board that we hadn't considered before.




Details can be found at our website.


Attachments:
2015_OurSolutionB93.sgf [1.35 KiB]
Downloaded 77 times

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by three amateurs)
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 29 posts ]  Go to page Previous  1, 2

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group