Author: Ricardo Gibert
Date: 18:43:51 09/21/99
Go up one level in this thread
On September 21, 1999 at 13:17:35, Robert Hyatt wrote: >On September 21, 1999 at 03:12:18, Ricardo Gibert wrote: > >>On September 20, 1999 at 19:36:26, José de Jesús García Ruvalcaba wrote: >> >>>On September 20, 1999 at 19:05:56, Jeremiah Penery wrote: >>> >>>>On September 20, 1999 at 16:15:46, James Robertson wrote: >>>> >>>>>My program only generates Queen and Knight promotions, as I have never seen a >>>>>position where a Bishop/Rook promotion was any good.... I have run across a few >>>>>nice Knight promotion positions, though. >>>> >>>>There are some positions where promoting to a Rook is the only winning move, as >>>>a Queen promotion would stalemate, and a Knight wouldn't be enough to be able to >>>>mate the opponent with. Unfortunately, I don't have any examples. :( >>>>In any case, such positions are VERY rare. >>>> >>>>Jeremiah >>> >>>Here there are some examples: >>>8/1P6/k7/8/1K6/8/8/8 w >>>8/k1P5/2K5/8/8/8/8/8 w >>>José. >>> >>>P.S. The Saavedra position is more interesting, but I do not have it handy. >> >>The following is the Saavedra position as I remember it. It could be this is not >>the exact position, but the idea is the same. My understanding is the position >>ocurred in a game, but was not played correctly: >> >>8/8/1KP5/3r4/8/8/8/k7 w - - 0 0 >> >>1.c7 Rd6+ 2.Kb5 Rd5+ 3.Kb4 Rd4+ 4.Kc3 (or 4.Kb3 Rd3+ 5. Kc2 Rd4 transposes) Rd1 >>5.Kc2 Rd4 6.c8R! (6.c8Q? Rc4+!) Ra4 7.Kb3 wins. > > >This isn't needed. from the tablebases: ??? It's needed when your opponent plays 3...Rd4+. Also, with additional material on the K-side (e.g. W: Pg4, h3; B: Pg5, h6), a program will not get its EGTB hit. Then it might be valuable (for a human anyway) to exploit those programs that do not under-promote. > >1. c7 Rd6+ 2. Kb5 Rd5+ 3. Kb4 Kb2 4. c8=Q Rd4+ 5. Kb5 Kb3 6. Qc5 >Rd8 7. Qc4+ Kb2 8. Qe6 Rd2 9. Kc4 Rc2+ 10. Kb4 Kc1 11. Qe1+ >Kb2 12. Qd1 Rc8 13. Qd7 Rb8+ 14. Kc4 Rg8 15. Qe6 Rg2 16. Qe5+ >Kc1 17. Qa1+ Kd2 18. Qb2+ Ke3 19. Qxg2 Kf4 20. Kd5 Ke3 21. Qg4 >Kd2 22. Kc4 Ke3 23. Kc3 Kf2 24. Kd3 Kf1 25. Ke3 Ke1 26. Qe2# >Qe2# 1-0 > >promoting to a queen works just fine. It is a forced mate in 26 from the >initial position...
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.