Lomonosov - what is the mate-distance...

[Paloma]

.
of this position:
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[d] 6k1/6rp/6p1/6N1/3B4/8/8/K7 b - - 0 3

black to move: 3...Rb7 and than? (pv-line please)

[MikeB]

.
of this position:
.
[d] 6k1/6rp/6p1/6N1/3B4/8/8/K7 b - - 0 3

black to move: 3...Rb7 and than? (pv-line please)

This information is now freely available on the internet - no need to ask for it.

https://syzygy-tables.info/?fen=6k1/6rp ... _b_-_-_0_1

then download the pgn file

[Event ""] [Site "https://syzygy-tables.info/?fen=6k1/6rp ... _b_-_-_0_1"] [Date "2019.09.27"] [Round "-"] [White "Syzygy"] [Black "Syzygy"] [Result "0-1"] [Annotator "syzygy-tables.info"] [FEN "6k1/6rp/6p1/6N1/3B4/8/8/K7 b - - 0 1"] [SetUp "1"] { DTZ 3 } 1... Rb7 2. Nf3 h6 { KBNvKRPP with DTZ -2 } 3. Ne1 g5 { KBNvKRPP with DTZ -4 } 4. Be3 Rb5 5. Nc2 h5 { KBNvKRPP with DTZ -4 } 6. Na3 Rb3 7. Nb1 g4 { KBNvKRPP with DTZ -2 } 8. Nd2 Rxe3 { KNvKRPP with DTZ -2 } 9. Nb1 g3 { KNvKRPP with DTZ -2 } 10. Nd2 g2 { KNvKRPP with DTZ -2 } 11. Nb1 h4 { KNvKRPP with DTZ -2 } 12. Nd2 h3 { KNvKRPP with DTZ -2 } 13. Nb1 h2 { KNvKRPP with DTZ -2 } 14. Nd2 g1=Q+ { KNvKQRP with DTZ -2 } 15. Ka2 h1=Q { KNvKQQR with DTZ -2 } 16. Nb1 Qxb1# { Checkmate } 0-1

[Paloma]

Online Syzygy is a mess. It's crap.
Not the shortest way to mate.

In your pgn 11.Nb1? is -8# (11...g3 8#), best is 11.Kb2 -12# (6 men Nalimov),
your 12.Nd2 (-6#) lost another move, best: 12.Kb2 -7# (12...g2 7#)
13.Nb1? best is 13.Kb1
After 13.Nb1 is g1Q mate in 4, not your 13...h4 (mate in 7)

In your pgn after 15.Nb1 is h2 wrong, best g1Q+
After your h2 is 16.Nc3 best, not your Nd2
18.Nb1 wrong, best is 18.Kb2 Qc1+ 19.Ka2 Qxd2#

Therfore i asket to Lomonosov.

[Paloma]

btw. 7...h5 is mate in 28 according to Houdini 6

so the syzygy line 16.Nb1 Qxb1# is a crap.

[MikeB]

Online Syzygy is a mess. It's crap.
Not the shortest way to mate.

In your pgn 11.Nb1? is -8# (11...g3 8#), best is 11.Kb2 -12# (6 men Nalimov),
your 12.Nd2 (-6#) lost another move, best: 12.Kb2 -7# (12...g2 7#)
13.Nb1? best is 13.Kb1
After 13.Nb1 is g1Q mate in 4, not your 13...h4 (mate in 7)

In your pgn after 15.Nb1 is h2 wrong, best g1Q+
After your h2 is 16.Nc3 best, not your Nd2
18.Nb1 wrong, best is 18.Kb2 Qc1+ 19.Ka2 Qxd2#

Therfore i asket to Lomonosov.

I had not looked closely - but you are correct - sorry.

[velmarin]

You have the free lomonosov app for android,
https://play.google.com/store/apps/deta ... ovtb&hl=en

[Paloma]

i don't have a smartphone

[Cumnor]

[Event "?"] [Site "?"] [Date "????.??.??"] [Round "?"] [White "?"] [Black "?"] [Result "0-1"] [SetUp "1"] [FEN "6k1/6rp/6p1/6N1/3B4/8/8/K7 b - -"] 1...Rb7 2.Nf3 h5 3.Ka2 Kf7 4.Ng5+ Ke7 5.Nf3 Rb5 6.Bc3 Rf5 7.Ng1 h4 8.Kb3 g5 9. Kc4 Ke6 10.Bd4 g4 11.Ne2 g3 12.Bb6 h3 13.Nxg3 h2 14.Bc7 Rf1 15.Nxf1 h1Q 16.Nd2 Qc1+ 17.Kd3 Qxc7 18.Nc4 Qd8+ 19.Kc3 Kd5 20.Nd2 Qc8+ 21.Kd3 Qe8 22.Kc2 Qe3 23. Nb3 Qe2+ 24.Kc3 Qc4+ 25.Kb2 Qd3 26.Na5 Qd2+ 27.Kb1 Qxa5 28.Kc1 Qa2 29.Kd1 Kd4 30.Kc1 Kd3 31.Kd1 Qd2# 0-1

Code: Select all

1	Rg7b7	31	6	h5	0
2	Rg7d7	34	7	Rg7f7	0
3	Rg7c7	37	8	Kg8f8	0
4	Rg7e7	52	9	Kg8h8	0
5	h6	0	10	Rg7a7	-38

[velmarin]

i don't have a smartphone

You can install it on PC, with an emulator like NOX, it also works.
https://www.bignox.com

[Paloma]

Many Thanks Cumnor.