Probably the longest “Rambling Rook” composition around

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peter
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Full name: Peter Martan

Re: Probably the longest “Rambling Rook” composition around

Post by peter »

Spliffjiffer wrote: Wed Apr 28, 2021 3:07 am yes, if u check only the last 10 moves or so (until the checkmate) its enough to have kingsquares set to 1 or 2 (as far as i can remember) but if you check the last say 20 moves to checkmate u need already 3 kingsquares to confirm yout MOJO analysis...anyting deeper in the tree needs at least these 3 ks as well at the least....the point of my "defender moves" is that Chest does not find 33. Bg3 (in the inferior 11...Rh5+ line i gave above) in reasonable time because it checks all kind of other moves instead...i dont get it eighter but one move later (move 34 onwards) it solvees these positions within seconds, hm,sprachlos...also after the 32...Rh4+? 33. Kg2 Rxh2+ line which is only -mate 100, it needs about 6 minutes here but its a halfway reasonable time with high chances to be the optimal mate imo but not sure of course
Thanks, will restart it from Black's side with defender moves and KS3 again, after 6 hours so far only depth 86 with KS2 from position after 1...Rg4+, so I guess with KS3 and one more ply it will take some longer even.
I'm still not a Chest- expert at all.
Gustav mit 2 Fluchtfeldern rechnet auch schon 6 Stunden ohne Erfolg, vielleicht liest ja Olaf Jenkner mit, der könnte für sein Programm vermutlich erst recht ein besseres Setting empfehlen, das nicht nur die Fluchtfelder vorgibt.
:roll:
Peter.
Spliffjiffer
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Location: Germany

Re: Probably the longest “Rambling Rook” composition around

Post by Spliffjiffer »

peter wrote: Wed Apr 28, 2021 9:01 am Thanks, will restart it from Black's side with defender moves and KS3 again, after 6 hours so far only depth 86 with KS2 from position after 1...Rg4+, so I guess with KS3 and one more ply it will take some longer even.
I'm still not a Chest- expert at all.
Gustav mit 2 Fluchtfeldern rechnet auch schon 6 Stunden ohne Erfolg, vielleicht liest ja Olaf Jenkner mit, der könnte für sein Programm vermutlich erst recht ein besseres Setting empfehlen, das nicht nur die Fluchtfelder vorgibt.
:roll:
i believe that Hobacle's solution is flawlessly correct...i mean he probably found all the best moves until checkmate imo...this would be #-172 if i remember well...if that is true, then neither Chest (it can solve problems only to a maximum lengh of 126 moves and not a single one more, ok 1 halfmove more if "defender moves" is checked) nor Gustav (here I am not sure but it solves problems to a maximum lengh of 170 moves i think) can solve Hobacle's #-172 !!!
all we can do is to combine the best of all worlds (speak to the author, use our own brain,use a promising engine, MOJO obviously eg and try to involve matesolver software when the probable solution comes into their horizons...which works here astonishing well when found the "correct" settings...but only whithin 126 moves in the case of Chest eg)

i dont know if i understand it well but from my pov neither Chest nor Gustav will find a mate after 1...Rg4+ (if #-172)
Wahrheiten sind Illusionen von denen wir aber vergessen haben dass sie welche sind.
Hobacle
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Re: Probably the longest “Rambling Rook” composition around

Post by Hobacle »

About the “Rambling Rook” problems:
fishpov wrote: Sat Apr 24, 2021 2:54 am [d]1r4Q1/7p/2N1B2k/7P/3Pp1P1/K1N1P2R/PP2PR2/8 b - - 0 1
.. Rb3+
Here's my solution of it.

[pgn][Event ""]
[Site ""]
[Date ""]
[Round ""]
[White ""]
[Black ""]
[Result "1-0"]
[FEN "1r4Q1/7p/2N1B2k/7P/3Pp1P1/K1N1P2R/PP2PR2/8 b - - 0 1"]
[SetUp "1"]

1... Rb3+ 2. Ka4 Rb4+ 3. Ka5 Rb5+ 4. Ka6 Rb6+ 5. Ka7 Rb7+ 6. Ka8 Ra7+ 7. Kb8
Rb7+ 8. Kc8 Rc7+ 9. Kd8 Rd7+ 10. Ke8 Re7+ 11. Kf8 Re8+ 12. Kf7 Re7+ 13. Kf6
Rf7+ 14. Ke5 Rf5+ 15. Kd6 Rd5+ 16. Ke7 Rd7+ 17. Kf8 Rd8+ 18. Kf7 Rd7+ 19. Ne7
Rxe7+ 20. Kf6 Rf7+ 21. Ke5 Rf5+ 22. Kd6 Rd5+ 23. Kc7 Rd7+ 24. Kb6 Rd6+ 25. Ka5
Rd5+ 26. Nb5 Rxb5+ 27. Ka6 Rb6+ 28. Ka7 Rb7+ 29. Ka8 Ra7+ 30. Kb8 Rb7+ 31. Kc8
Rc7+ 32. Kd8 Rd7+ 33. Ke8 Re7+ 34. Kf8 Re8+ 35. Kf7 Re7+ 36. Kf6 Rf7+ 37. Ke5
Rf5+ 38. Kd6 Rd5+ 39. Kc7 $1 39... Rd7+ 40. Kb6 Rd6+ 41. Ka5 Rd5+ 42. Kb4 Rb5+
43. Kc3 Rb3+ 44. Kd2 Rxb2+ 45. Kc3 Rb3+ 46. Kc4 Rc3+ 47. Kb4 Rc4+ 48. Ka3 Ra4+ 49. Kb2 Rxa2+ 50. Kb3
Rb2+ 51. Kc4 Rc2+ 52. Kd5 Rc5+ 53. Kxe4 Re5+ 54. Kd3 Rxe3+ 55. Kc4 Rc3+ 56. Kb4
Rc4+ 57. Ka3 Ra4+ 58. Kb2 Ra2+ 59. Kc3 Rc2+ 60. Kd3 Rc3+ 61. Ke4 Re3+ 62. Kd5
Re5+ 63. Kc6 Rc5+ 64. Kd7 Rd5+ 65. Kc8 Rc5+ 66. Kd8 Rd5+ 67. Bd7 Rxd7+ 68. Ke8
Re7+ 69. Kf8 Re8+ 70. Kf7 Re7+ 71. Kf6 Re6+ 72. Kf5 Re5+ 73. Kf4 Re4+ 74. Kg3
Re3+ 75. Kh2 Rxh3+ 76. Kg1 *
[/pgn]

There's a mistake in the solution on Yacpdb: https://www.yacpdb.org/#search/MXI0UTE3 ... MS8xLzA=/1
39. Kc6 and some moves after it, such as 44. b4, are a waste of time. 39. Kc7! is the right move.

After 76. Kg1, Black has several different choices to get into the endgame and I was not sure which one was the best. So I stoped here.
Anyhow its DTM is unlikely to be longer than my acoustic version's(#123).
Hobacle
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Full name: Nott Q Suree

Re: Probably the longest “Rambling Rook” composition around

Post by Hobacle »

Hobacle wrote: Wed Apr 28, 2021 11:00 am There's a mistake in the solution on Yacpdb: https://www.yacpdb.org/#search/MXI0UTE3 ... MS8xLzA=/1
The right link: http://www.yacpdb.org/#search/MXI0UTE3c ... MS8xLzA=/1


Hobacle wrote: Wed Apr 28, 2021 11:00 am 39. Kc6 and some moves after it, such as 44. b4, are a waste of time. 39. Kc7! is the right move.
Because 39. Kc6 Rd6+ 40. Kb5 allow the Black Rook to get into Rank C prematurely by 40. ... Rb6+! 41. Kc4 Rc6+ .
After 39. Kc7 Rd7+ 40. Kb6 , 40. ... Rb7+ will lose in a short time.



I haven't found any “Rambling Rook” problem which has consecutive checking moves longer than my acoustic version's(122) besides mine up to now.
Hobacle
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Joined: Thu Mar 04, 2021 3:57 pm
Full name: Nott Q Suree

Re: Probably the longest “Rambling Rook” composition around

Post by Hobacle »

About 16v2 compositions:

Dann Corbit gave me 1703 ones, this composition is probably the longest one among them:

[d]q4b2/2p2p1p/3r1p1p/8/8/1p3Q1p/krp5/nbK2n2 w - - acd 105

According to http://www.yacpdb.org/#search/cTRiMjJwM ... LzEvMA==/1, this one is #86.