Saturday, 27 July 2019

Study 174

Árpád Rusz
Iriarte MT
2019

Draw

1. Rd2+ 1. Rxf4? Ke5+ -+ 1... Ke5 1... Kc5 2. Rxc4+! (2. Rxd6? Rh1+ 3. Kd2 Rxc1 4. Rf6 Rf1! 5. Ke2 Rh1 6. Rxf4 Kb4 -+) 2... Kxc4 3. Rxd6 = 2. Rxd6 2. Rxc4? Rh1+ 3. Kc2 Ra6 -+ 2... Rh1+! 2... Kxd6 3. Rxc4 = 3. Kd2 Rxc1 4. Rc6 4. Kxc1? Kxd6 -+ 4... Kd5! 4... f3!? 5. Kxc1 f2 6. Rc5+ Ke4 7. Rxc4+ Kf3 8. Rc3+ Kg2 9. Rc2 =

5. Rf6 Rf1 6. Ke2! Ke5! 6... c3!? 7. Kxf1 c2 8. Rf5+ Kd4 9. Rxf4+ Kc3 10. Rf3+ Kb2 11. Rf2 = 7. Rc6 Rc1 8. Kd2! Kd5! 9. Rf6 = positional draw - perpetual attack

Study 173

Árpád Rusz
Iriarte MT
2019

White wins

1. g7 1. Rd8? Ra1! 2. Rxd6 Ra7+ = 1... Rh7 2. Rg8 Kxd5


systematic movement

3. Kb6! 3. Kd7? Ke5 4. Re8+ Kf6 = 3... Kd4 3... Ke6 4. Re8+ +- 4. Kc6 4. Kb5? Rh5+ 5. Kc6 Rg5 6. Kxd6 Rg6+ 7. Ke7 Ke5 8. Kf7 Rf6+ = 4... d5 5. Kb5 Kd3 6. Kc5 d4 7. Kb4 Kd2 8. Kc4 d3 9. Kb3 Kd1 10. Kc3! 10. Kb2? d2 = mutual zugzwang 10... d2 11. Kb2 mutual zugzwang 11... Rh6 11... Ke2 12. Re8+ +- 12. Rb8! +- Switchback 12. Rd8? Rb6+ =

Friday, 26 July 2019

Study 172

Aleksandr Zhukov & Árpád Rusz
64
2019


White wins

1. Kd7!! Paradoxically, the king not only it doesn't capture the c-pawn, it also doesn't get closer to the f-pawn! 1. Kxc7? f5 2. Kd6 f4 =; 1. Ke7? c5 2. Kd6 c4 3. Rh4+ Kd3 4. Kd5 c3 5. Rh3+ Kd2 6. Kd4 c2 7. Rh2+ Kd1 8. Kd3 c1=N+! =

Main A:
1... c5 2. Kc6 f5 3. Rf8! 3. Kb5? f4 4. Rf8 Ke3 5. Kxc5 f3 =


chameleon echo

3... c4 4. Kb5 c3 5. Ka(b)4 c2 6. Rc8 f4! 6... Kd3 7. Kb3 f4 8. Rd8+ Ke2 9. Kxc2 f3 10. Re8+ +- 7. Kb3! f3 8. Kxc2 f2 9. Rf8 Ke3 10. Kd1 +-


chameleon echo

Main B:
1... f5 2. Ke6 Ke4 2... f4 3. Kf5 +- 3. Kf6 c5 4. Rc8!


chameleon echo

4... f4 5. Kg5 f3 6. Kg(h)4 f2 7. Rf8 c4! 7... Ke3 8. Kg3 c4 9. Re8+ Kd2 10. Kxf2 c3 11. Rd8+ +- 8. Kg3! c3 9. Kxf2 c2 10. Rc8 Kd3 11. Ke1 +-


chameleon echo

Study 171

Árpád Rusz
Bron-110 MT
2019
3rd/4th Honourable Mention

White wins

1. Bxa5+ 1. e8=Q? Qb3+! (1... Kd1+? 2. Be2+! +-) 2. Kxa1 Qd1+ 3. Kb2 (3. Ka2?? Kc1+ -+) 3... Qc2+ 4. Ka1 Qd1+! perpetual check 1... Kd1+ 1... Ke3+ 2. Ka3 Nc2+ 3. Ka4 +- 2. Bd2! unguarded guard sacrifice 2. Kxa1?? is wrong because the a8 rook doesn't protect the a3 square. 2... Qa3+ -+ 2... Nd3+! 2... Rxd2+ 3. Kxa1 After the bishop sacrifice, the a3 square is protected. 3... Qa3+ 4. Rxa3 +- 3. Bxd3 Rxd2+! 3... Rxf6 4. e8=Q +-

Thematic try:
4. Kxa1? Qxd3! mutual zugzwang. Paradoxically, it will be bad for white that the pawn is going to be promoted! 5. e8=Q 5. Ra2 Rxa2+ 6. Kxa2 Qd5+ 7. Ka3 Qa5+ 8. Kb3 Qb5+ 9. Kc3 Qc5+ 10. Kd3 Qc2+ 11. Ke3 Qc3+! 12. Qxc3 stalemate 5... Qc3+! 6. Qxc3 Ra2+! 7. Kb1 7. Rxa2/Kxa2 stalemate 7... Rb2+! 8. Ka1 Ra2+ perpetual check/stalemate

Solution:
4. Kb1!! Qxd3+ 5. Kxa1!


mutual zugzwang

5... Rc2 5... Ra2+ 6. Kxa2! (6. Rxa2? Qc3+! 7. Rb2 (7. Qxc3 stalemate) 7... Qxf6 8. e8=Q Qa6+ 9. Kb1 Qd3+ 10. Ka2 Qa6+ 11. Kb3 Qb6+ 12. Ka3 Qe3+! 13. Qxe3 stalemate) 6... Qd5+ 7. Kb2 +- 6. Rd8 Rc1+ 7. Ka2 Rc2+ 8. Qb2! Rxb2+ 9. Kxb2 +-

Study 170

Árpád Rusz
Shakhmatnaya Kompozicia
2019

Draw

1. Nxe6! Threatening with checkmate on c7. Thematic try: 1. Nf4+? g2 2. Bxg2+ Rxg2 3. N8xe6 (3. Nxg2 Nf7 4. Nxe6 Qc4+ 5. Nc7+ Qxc7+ 6. Kxc7 Nxh6 -+) 3... Nxe6 4. Nxe6 Qg4! -+ Black pins the knight. The g4 square was empty because the rook managed to move away. 1... Nxe6 2. Nf4+ g2 3. Nxe6! White again is threatening to give checkmate on c7. The knight cannot be pinned by Qg4. Letting the rook to move away from g4 is again a mistake: 3. Bxg2+? Rxg2 4. Nxe6 Qg4! -+ 3... Qc4+ 3... gxh1=Q?? 4. Nc7# 4. Nc7+ Qxc7+ 5. Kxc7 Rxg7+! 5... Bb8+ 6. Kd8! The white king leaves the c8 square empty. 6... gxh1=Q 7. Qa6+ Ba7 8. Qc8+ Bb8 9. Qa6+ perpetual check 6. Qxg7 Bb8+

7. Kc6!! Triangulation. White lets black to promote the pawn with check. Thematic try: 7. Kb6? gxh1=Q -+ mutual zugzwang 7... gxh1=Q+ 8. Kb6! Focal Theme. The black queen has to keep an eye on both b7 and a1.


mutual zugzwang

8... Qg1+! Moving the knight would be very bad: 8... Nf1?? 9. Qa1+ Ba7+ 10. Qxa7#; 8... Nf3?? 9. Qb7# 9. Qxg1 Ba7+ 10. Kc7 Bxg1 11. b6 = The knight is again in a wrong place blocking the h2 square for the bishop.

Thursday, 25 July 2019

Study 169

Árpád Rusz
2019
RCS blog
dedicated to John Roycroft

Draw

1. Kb3! 1. Kb2? Rg1 2. Kxa2 Rxg4 -+ 1... Rg1 1... Rb1+ 2. Kxa2 Rb5 3. Rb7 = 2. Rxa2! Rg3+! 2... Rxg4 3. Ra6 Rxg5 4. Rxb6 Kf7 5. Kc4 (5. Kc3? Rd5 -+) 5... Rg3 6. Kd4 = (6. Kd5? Rg4 7. Ke5 Kg7 -+) 3. Kc4! 3. Kc2? Rg2+ -+ 3... Rxg4+ 4. Kd5! Rxg5+ 4... Ke7 5. Ra7+ = 5. Ke6! Ra5 6. Rh2!

6... Kd8 7. Kd6 7. Rh8+? Kc7 -+ 7... Rh5 8. Ra2! Ke8 9. Ke6 Ra5 10. Rh2 positional draw - perpetual threat of checkmate

Wednesday, 3 July 2019

Study 168

Vlaicu Crişan & Árpád Rusz
The Problemist
2019

Draw

1. f5! 1. a7? Qe7+/Qd8+ 2. Kh6 Qf8+ 3. Kg5 a2 4. Qxa2 Qe7+/Qd8+ 5. Kh6 Qh4#

Main A:
1... Qd8+ 2. f6 Qa5+ 2... Qd5+ 3. Kh6 Qh1+ 4. Kg5 Kh7! 5. Kf4 (5. a7? Qh6#) 5... Qd5 6. a7 a2 7. Qh2(4)+ 7... Kg8 8. Qh6!! Q sacrifice 8... Qd2+ (8... a1=Q?? 9. Qg7#) 9. K~ Qxh6 10. a8=Q+ = 3. Kh6 Qxa6 3... a2 4. Qh2! Qd8 5. Kg5+! (5. Qxa2? Qxf6 6. g5 Qg7#) 5... Kg8 6. Qxa2 +-

4. Qa7!! Q sacrifice 4. Qc5? Qa8! -+ 4... Qxa7 5. g5! a2 stalemate

Main B:
1... Qe7+ 2. f6 Qe5+ 3. Kh4! 3. Kh6? a2! -+ 3... g5+ 4. Kh3! 4. Kh5? a2! 5. Qxa2 Qxf6 6. Qd5 Qg6# 4... Qd5 5. a7 a2

6. Qc5!! Q sacrifice 6. Qd4? Qh1+ 7. Kg3 a1=Q -+ The white queen cannot reach f8. 6... Qxc5 6... Qh1+ 7. Kg3 a1=Q?? 8. Qf8+! Kh7 9. Qg7# 7. a8=Q+ Kh7 8. Qxa2 =

Watch this study on a dynamic board! Click here!

Study 167

Mario Micaloni & Árpád Rusz
Benkő-90 JT
2019
2nd Prize

White wins

1. e5 Nc3 2. Nf6! 1st knight opposition 2. Kd7? Ne4! (2... Nxa4? 3. Kc6 +-) 3. Kc6 Ng5 = 2... Kc4 2... Nxa4 3. Kd6 Kd4 4. e6 Nb6 5. Kc7 Ke5 6. e7 +- 3. Kd6 Ne2 4. Nh5! 2nd knight opposition 4... Nd4 5. Ng7! 3rd knight opposition 5... Kb4 1st cyclic zugzwang - WTM. In order to win, white has to reach the same position but with BTM. A move is lost by a king triangulation (3 moves) plus a knight switchback (2 moves) while the black knight moves only 4 times.


cyclic zugzwang - WTM

6. Kd5 Ne2 7. Nh5! Nc3+ 8. Kc6! Ne2 9. Kd6 Nd4 10. Ng7! White has managed to transfer the move to black but black has a tempo move. 10... a5


cyclic zugzwang - WTM

11. Kd5 Ne2 12. Nh5! Nc3+ 13. Kc6 Ne2 14. Kd6 Nd4 15. Ng7! White ends the second cycle but black has another tempo move. 15... a6 15... Nb5+!? 16. axb5 a4 17. Nf5/Ne6 a3 18. Nd4 Kc3 (18... a2 19. Nc2+ Kc3 20. Na1 Kb2 21. e6 Kxa1 22. e7 Kb2 23. e8=Q +-) 19. b6! axb6 20. Nb5+ +-


cyclic zugzwang - WTM

16. Kd5 Ne2 17. Nh5! Nc3+ 18. Kc6 Ne2 19. Kd6 Nd4 20. Ng7! The third cycle finishes. Black has no more tempo moves...


cyclic zugzwang - BTM

20... Kxa4 21. Kc5 Nb3+ 22. Kc4 Nd2+ 23. Kd5 +- 20... Kc4 21. e6 Nxe6 22. Nxe6 Kb4 23. Nc5 +-

Watch this study on a dynamic board! Click here!

Study 166

Árpád Rusz
Benkő-90 JT
2019
1st Commendation

Draw

1. Rc3! 1. Re4? Kb1! Triangulation 2. Kb3 (2. Rc4 Kb2 -+ mutual zugzwang) 2... Rf3+ 3. Ka4 Kc2 4. Kxa5 Kd3 5. Rh4 Rf5+ 6. Kb4 Ke2 7. Kc3 Kxf2 8. Kd3 Kg3 9. Rh1 h4 -+ 1... Kb2 1... Kb1 2. Kb3 Rxf2 3. Rh3 = 2. Rc4! mutual zugzwang 2... Rg5 2... Rxf2 3. Rh4 (or 3. Kxa5) 3... Rf5 4. Rxh5! Rxh5 stalemate 3. Rc6!! mutual zugzwang 3... Rd5 3... h4 4. Rh6 Rg4+ 5. Kxa5 Kc3 6. Kb6! Kd4 7. Rf6 Ke5 8. Rf3 Ke4 9. Rh3 = 4. Rc8! mutual zugzwang 4. Rc7? Re5! mutual zugzwang 5. Rc6 Rg5! mutual zugzwang 6. Rc7 h4 7. Rh7 Rg4+ 8. Kxa5 Kc2(3) 9. Kb6 Kd3 10. Kc7 Ke4! Now the e4 square was empty! 11. Rf7 Rf4 12. Rh7 Kf3 -+ 4... Re5 5. Rc7! mutual zugzwang 5... h4 5... Rf5 6. Rc4 positional draw on 4 pairs of corresponding squares

6. Rh7 Re4+ 7. Kxa5 Kc3 8. Kb6! Kd3 9. Kc7! The white king is hiding from lateral checks. 9. Kc5? Ke2 10. Rf7 Re5+ 11. Kd4 Rh5 -+ 9... Ke2 The e4 square was blocked! 10. Rf7 h3 11. Rh7 = The pawn cannot be defended.

Watch this study on a dynamic board! Click here!

Study 165

Árpád Rusz
Korányi MT
2018
1st/2nd Prize

White wins

1st thematic try:
1. Qd1+? Bg4 2. Nf3 Bc5+! 2... c2? 3. Bxc6!! Queen sacrifice 3... cxd1=Q 4. Be8# 3. Kb8 3. Kb7 c2! -+ 3... Bd6+ 4. Ka7 Bc5+ perpetual check.

The king cannot escape from the checks because the corner square is blocked.

Solution:
1. Bxc6! Bc5+! 1... Bxc6 2. Qxc6 +-

2nd thematic try:
2. Kb7? h1=Q 3. Qd1+ Bg4 4. Nf3?

4... Bc8+! Bishop sacrifice. Black is unblocking the g4 square before taking the queen! 5. Kxc8 Qxd1 6. Be8+ Kg4! -+; 2. Kb8? h1=Q 3. Qd1+ Bg4 4. Nf3? Qh2+! -+

2. Ka8!! The corner square has been unblocked, so the white king finds a nice hiding place there. 2... h1=Q! Cross-pin

3. Qd1+ 3. Bxh1? Bxa4 -+ 3... Bg4!

4. Nf3!! Cross theme & Queen sacrifice 4... Qxd1 4... Bxf3 5. Bxf3+ +- 5. Be8#

Watch this study on a dynamic board! Click here!

Study 164

Árpád Rusz
Korányi MT
2018

White wins

1. Ra6 Re3 1... Rg4+ 2. Kd5 Rxa6 3. Rxa6 Rf4 4. Ke5 Rf3 5. c4 h3 6. c5 h2 7. Ra2+ Kg3 8. Rxh2! rook sacrifice 8... Kxh2 9. c6 +- 2. Rf1+! rook sacrifice 2... Kxf1 3. Kxe3 Rf2 3... Rxc2 4. f7 Rf2 5. Ra1+ Kg2 6. Ra2! rook sacrifice 6... Rxa2 7. f8=Q +-; 3... h3 4. Ra1#; 3... Re2+ 4. Kf3 Rf2+ 5. Kg4 +- 4. Ra1+ 4. Ra4? h3 5. Rh4 Rxc2! 6. Rxh3 Rc3+ = 4... Kg2

5. Rh1!! rook sacrifice 5... Rf3+ 5... Kxh1 6. Kxf2 +-; 5... Rxf6 6. Rxh4 +- 6. Ke4 h3 6... Rxf6 7. Rxh4 Rc6 8. Kd3 +- 7. Rh2+! rook sacrifice 7... Kg3 8. Rxh3+! rook sacrifice 8... Kxh3 9. Kxf3 +-

Watch this study on a dynamic board! Click here!

Study 163

Árpád Rusz
Chess Olympiad
2018
Special Commendation

White wins

1. Nc2+! 1. Rf2? Rc6+! (1... Rxh6? 2. Rxa2+! bxa2 3. Nc2#; 1... b2+? 2. Rxb2 Rc6+ 3. Rc2 Rxh6 (3... Rxc2+ 4. Nxc2#) 4. Rxa2#) 2. Nxc6 b2+ 3. Rxb2 stalemate 1... bxc2 2. h7 Rf6! 2... Rh6 3. Rf1! Rxh7 4. Kxc2#

3. Rf7!! mutual zugzwang 3. h8=Q? stalemate; 3. h8=R? Rxf8 4. Rxf8 stalemate; 3. Rg8? Rf1+! (3... Rh6? 4. Rg1 Rxh7 5. Kxc2#) 4. Kxc2 Rf2+ 5. Kb3 Rf3+ 6. Kc2 Rf2+ perpetual check 3... Rf1+! 4. Kxc2 Rf6! Black managed to lose a tempo but the position is slightly changed: the first rank now it is open. 4... Rf2+ 5. Kb3 Rb2+ 6. Ka3 (6. Kc3?! Rc2+! 7. Kb3 Rb2+) 6... Kb1 7. Rf1+ Kc2 8. h8=Q +-; 4... Rc1+ 5. Kb3! Kb1 6. h8=Q a1=Q 7. Qh7+ +-

5. h8=R! 5. Rd7? Rc6+ 6. Kb3 Rb6+ 7. Ka3 Ra6+ 8. Kb3 Rb6+ perpetual check 5... Rxf7 6. Rh1+ Rf1 7. Rxf1#

Watch this study on a dynamic board! Click here!

Tuesday, 18 June 2019

WCCI 2016-18 Results

The results of the WCCI has been published.

1st Place: Oleg Pervakov (RUS)
2nd Place: Martin Minski (GER)
3rd Place: Steffen Slumstrup Nielsen (DEN)

Monday, 15 April 2019

Syzygy Endgame Explorer v. 0.2

Syzygy Endgame Explorer v. 0.2 has been released!
Besides bugfixes, it includes some new features like searching for symmetrical positions. SEE now also accepts a pgn file as an input so it can search e.g. the van der Heijden database for anticipations.
You can find the download link here.

Added new features:

  • Comments after any line are allowed
  • Any "sq1-sq2" combination (e.g. "a1-a4", "a1-e1", or "a1-c3") can be used to give a set of squares along a file, rank or diagonal
  • A rectangular region can be given by four squares (e.g. "c5-f5-f3-c3")
  • Use "~e4", "~fileD", "~rank4" to exclude some squares
  • The [BlackKing], [BlackQueen], ..., [WhitePawn] keywords now can use all square collections just like [Piece1], ..., [Piece7]. Additionally, they can use the initial squares of the pieces ("sq1", "sq2",..., "sq7" or "~sq1", "~sq2", ..., "~sq7")
  • New keyword [Symmetry] for setting various symmetry axes
  • New keywords [Identical] and [Different]
  • . These are replacing the functionality of [RememberFEN], [RepeatPosition] and [NotRepeatPosition] which were removed (see the modified Example 22).
  • [InputTXT] was changed to [Input] and now it accepts both text (FEN lists) and pgn files.
  • Now [FEN] and [FENList] accepts both stripped and standard FENs
  • New [Eval] values like "not_draw" and "loss/loss"
  • [OutputScreen "diag"] will output the found positions not only with FENs but also in ASCII diagrams

Example 28

******ex28.txt*******
[Tablebase "KPkp"]

[Position "1"]
[Eval "loss/loss"] //full point mutual zugzwangs
********************


full point mutual zugzwang

Example 29

******ex29.txt*******
[Tablebase "KPkp"]
[OutputScreen "diag"]

[Position "1w"]
[Eval "win"]
[OnlyMove "yes"]
[MovedPiece "K"]
[Capture "no"]
[Check "no"]

[Position "1b"]

[Position "2w"]
[Eval "win"]
[OnlyMove "yes"]
[MovedPiece "K"]
[Capture "no"]

[Position "2b"]
[WhiteKing "sq1"] //Switchback
********************


Switchback

1. Kc6! a5 2. Kb5! +-

Example 30

******ex30.txt*******
//Place interchange
[Tablebase "KPkp"]

[Position "1w"]
[Piece1 "half"]
[Eval "win"]
[OnlyMove "yes"]

[Position "1b"]

[Position "2w"]
[Eval "win"]
[OnlyMove "yes"]

[Position "2b"]

[Position "3w"]
[Eval "win"]
[OnlyMove "yes"]

[Position "3b"]
[WhiteKing "sq2"]
[WhitePawn "sq1"]
********************

1. Kb5! e5 2. c5 e4 3. Kc4! +- Compared to the initial position, the white king and pawn have switched positions.

Example 31

******ex31.txt*******
//During the solution, all white pieces should move.
[Tablebase "KPk"]

[Position "1w"]
[Eval "win"]
[OnlyMove "yes"]

[Position "1b"]

[Position "2w"]
[Eval "win"]
[OnlyMove "yes"]

[Position "2b"]
[WhiteKing "~sq1"] The white king has left its initial square.
[WhitePawn "~sq2"] The white pawn also has left its initial square.
********************

1. Kg7! Kf5 2. h5 +-

Example 32

******ex32.txt*******
//Duplex Excelsior
[Tablebase "KPkp"]

[Position "1w"]
[Piece2 "rank2"]
[Symmetry "d5-e5-e4-d4"] //We are looking for a point symmetric position.
[Eval "win"]
[OnlyMove "yes"]

[Position "1b"]

[Position "2w"]
[WhitePawn "rank4"]
[Eval "win"]
[OnlyMove "yes"]

[Position "2b"]

[Position "3w"]
[WhitePawn "rank5"]
[Eval "win"]
[OnlyMove "yes"]

[Position "3b"]

[Position "4w"]
[WhitePawn "rank6"]
[Eval "win"]
[OnlyMove "yes"]

[Position "4b"]

[Position "5w"]
[WhitePawn "rank7"]
[Eval "win"]
[OnlyMove "yes"]

[Position "5b"]
[WhiteQueen "rank8"] //Excelsior to queen
********************


Win (DUPLEX)

White to move:
1. b4 g5 2. b5 g4 3. b6 g3 4. b7 g2 5. b8=Q g1=Q 6. Qh8+ Kg6 7. Qg8+ +-

Black to move:
1... g5 2. b4 g4 3. b5 g3 4. b6 g2 5. b7 g1=Q 6. b8=Q Qa1+ 7. Kb3 Qb1+ -+

Example 33

******ex33.txt*******
// Finding Saavedra
[Tablebase "KPkr"]
[Input "heijden.pgn"]

[Position "1w"]
[Piece1 "b6"]
[Piece2 "c6"]
[Piece3 "a1"]
[Piece4 "d5"]
********************

With ordinary pgn files, only the initial positions will be searched. One needs a specially prepared pgn file which can be searched everywhere. This has a fen string added as a comment after each move. Use pgn-extract with --fencomments and --commentlines to prepare such a pgn file.

[Event "Glasgow Weekly Citizen#414 (m)"]
[Site "?"]
[Date "1895.05.04"]
[Round "?"]
[White "Saavedra=F Barbier=G"]
[Black "(+0300.10b6a1)"]
[Result "1-0"]
[EventDate "1895.??.??"]
[SetUp "1"]
[FEN "8/8/1KP5/3r4/8/8/8/k7 w - - 0 1"]
[PlyCount "13"]

1. c7
{ 8/2P5/1K6/3r4/8/8/8/k7 b - - 0 1 }
1... Rd6+
{ 8/2P5/1K1r4/8/8/8/8/k7 w - - 1 2 }
2. Kb5
{ 8/2P5/3r4/1K6/8/8/8/k7 b - - 2 2 }
(2. Kb7 $2
{ 8/1KP5/3r4/8/8/8/8/k7 b - - 2 2 }
2... Rd7 $11
{ 8/1KPr4/8/8/8/8/8/k7 w - - 3 3 }
) 2... Rd5+
{ 8/2P5/8/1K1r4/8/8/8/k7 w - - 3 3 }
3. Kb4
{ 8/2P5/8/3r4/1K6/8/8/k7 b - - 4 3 }
3... Rd4+
{ 8/2P5/8/8/1K1r4/8/8/k7 w - - 5 4 }
4. Kb3
{ 8/2P5/8/8/3r4/1K6/8/k7 b - - 6 4 }
(4. Kc3
{ }
{ 8/2P5/8/8/3r4/2K5/8/k7 b - - 6 4 }
4... Rd1
{ 8/2P5/8/8/8/2K5/8/k2r4 w - - 7 5 }
5. Kc2
{ 8/2P5/8/8/8/8/2K5/k2r4 b - - 8 5 }
) 4... Rd3+
{ 8/2P5/8/8/8/1K1r4/8/k7 w - - 7 5 }
5. Kc2
{ 8/2P5/8/8/8/3r4/2K5/k7 b - - 8 5 }
5... Rd4
{ 8/2P5/8/8/3r4/8/2K5/k7 w - - 9 6 }
6. c8=R $1
{ 2R5/8/8/8/3r4/8/2K5/k7 b - - 0 6 }
(6. c8=Q $2
{ 2Q5/8/8/8/3r4/8/2K5/k7 b - - 0 6 }
6... Rc4+ $1
{ 2Q5/8/8/8/2r5/8/2K5/k7 w - - 1 7 }
7. Qxc4
{ stalemate }
{ 8/8/8/8/2Q5/8/2K5/k7 b - - 0 7 }
) 6... Ra4
{ 2R5/8/8/8/r7/8/2K5/k7 w - - 1 7 }
7. Kb3
{ 2R5/8/8/8/r7/1K6/8/k7 b - - 2 7 }
1-0

With a file prepared like this, the search will find two additional examples in the van der Heijden database where the Saavedra position was reached during play.

******ex34.txt*******
// Finding the Conrady positions
[Tablebase "KRknp"]
[OutputPGN "KRknp_D23.pgn"]

Move 1:
[Position "1w"]
[Piece5 "h6"]
[Eval "win"]
[OnlyMove "yes"]
[Position "1b"]
[Eval "loss"]

Move 2:
[Position "2w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "2b"]
[Eval "loss"]

Move 3:
[Position "3w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "3b"]
[Eval "loss"]

Move 4:
[Position "4w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "4b"]
[Eval "loss"]

Move 5:
[Position "5w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "5b"]
[Eval "loss"]

Move 6:
[Position "6w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "6b"]
[Eval "loss"]

Move 7:
[Position "7w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "7b"]
[Eval "loss"]

Move 8:
[Position "8w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "8b"]
[Eval "loss"]

Move 9:
[Position "9w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "9b"]
[Eval "loss"]

Move 10:
[Position "10w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "10b"]
[Eval "loss"]

Move 11:
[Position "11w"]
[Piece1 "half"]
[Eval "win"]
[OnlyMove "yes"]
[Position "11b"]
[Eval "loss"]

Move 12:
[Position "12w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "12b"]
[Eval "loss"]

Move 13:
[Position "13w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "13b"]
[Eval "loss"]

Move 14:
[Position "14w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "14b"]
[Eval "loss"]

Move 15:
[Position "15w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "15b"]
[Eval "loss"]

Move 16:
[Position "16w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "16b"]
[Eval "loss"]

Move 17:
[Position "17w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "17b"]
[Eval "loss"]

Move 18:
[Position "18w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "18b"]
[Eval "loss"]

Move 19:
[Position "19w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "19b"]
[Eval "loss"]

Move 20:
[Position "20w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "20b"]
[Eval "loss"]

Move 21:
[Position "21w"]
[Piece1 "half"]
[Eval "win"]
[OnlyMove "yes"]
[Position "21b"]
[Eval "loss"]

Move 22:
[Position "22w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "22b"]
[Eval "loss"]

Move 23:
[Position "23w"]
[Eval "win"]
[OnlyMove "yes"]
[Position "23b"]
[Eval "loss"]
********************

6 positions were found:
8/8/7p/7n/3R4/8/k7/2K5 w - - 0 1
8/8/7p/7n/3R4/8/k7/3K4 w - - 0 1
8/8/7p/7n/k7/8/2K5/3R4 w - - 0 1
8/8/7p/7n/k7/8/2KR4/8 w - - 0 1
8/8/7p/7n/k7/3R4/2K5/8 w - - 0 1
3R4/8/7p/7n/k7/8/2K5/8 w - - 0 1

One of them is what Helmut Conrady has published in 2003 (Computer Schach und Spiele, Vol. 2, No. iv-v) as being the longest AUM (absolutely unique move) sequence in the tablebases up to 5 men:

Helmut Conrady
Computerschach und Spiele
2003

White wins

1. Rd4+ Ka3 2. Kd3 Kb3 3. Rd6 Kb4 4. Kd4 Nf4 5. Rb6+ Ka5 6. Rf6 Ne2+ 7. Kc4 Ng3 8. Rg6 Ne4 9. Kd4 Nd2 10. Rg2 Nf3+ 11. Kc5 Ka6 12. Rg6+ Kb7 13. Kd5 h5 14. Rh6 h4 15. Rf6 Ne1 16. Rf1 Nc2 17. Rb1+ Ka6 18. Rb2 Ne1 19. Ke4 h3 20. Rb1 Nc2 21. Kd3 Na3 22. Ra1 h2 23. Rxa3+ +-

Thursday, 11 April 2019

Study 162

Árpád Rusz
Internet (RCS blog)
2019

Draw

1. Kb7 Bc1 1... Kb1 2. Ne4! f1=Q 3. Nd2+ =; 1... Be5 2. Nf1 Kb2 3. Kc6 Kc3 4. Kd5 = 2. Kc6 Kb2 2... Bf4 3. Nf1 Kb2 4. Kd5 Kc3 5. Ke4 = 3. Kd5 Kc2 4. Ke4 Kd1 5. Kf3 Ke1 6. Kg2 Bf4 7. Nf1 Ke2 8. Kh1!


corner-to-corner manoeuvre

8... Kf3 8... Kxf1 stalemate

9. Ng3! Be5 9... Kxg3 stalemate; 9... Bxg3 stalemate 10. Nf1 Bf4 11. Ng3! positional draw - fortress

Watch this study on a dynamic board! Click here!

(162a)
J. Kling
1868

Draw

1. Ne5+! Bxe5 2. Ng3! Bf4 2... Bxg3 stalemate 3. Nf1 Ke2 4. Kg2 Ke1 5. Kh1! Kd1 5... Kxf1 stalemate 6. Kg2 Ke2 7. Kh1! Kf3 8. Ng3! Bxg3 stalemate 8... Kxg3 stalemate

(162b)
Mario G. Garcia
Hlinka-65 JT
- Section B -
2019
Special Honourable Mention

Draw

1. Na5+ Kd5 2. Nc6 Bc5 3. Nd8 f5 4. Nf7 Be7 5. Kd7 Bf6 6. Nh6 f4 7. Ng4 Bh4 8. Nh2 Ke4 9. Ke6Be1 10. Kf6 Bg3 11. Ng4 Bh4+ 12. Kg6 f3 13. Kh5 Be7 14. Nh2 f2 15. Kg4 Ke3 16. Kh3 Ke2 17. Kg2 Bd6 18. Nf1 Bf4 19. Kh1! Kf3 19... Kxf1 stalemate 20. Ng3! Bxg3 stalemate