Monday, May 04, 2015

Bank Holiday Monday

White to play

I am unwell.  Not in the Jeffrey Bernard 'pissed in a ditch' kind of a way and not in any kind of serious way, but unwell nonetheless. Unwell enough to not really feel like writing the post that I was going to write for today.

So I’m not going to. Here’s a simple position instead.

White to play. With best play should it be a win or can black hold the draw?

King and pawn Index


an ordinary chessplayer said...

What, anonymous hasn't looked this up in a tablebase yet?

Anonymous said...

The extra resources in forcing the opposing King back gained from having the spare pawn should make this a win. A tablebase will show you the exact technical method.

Put the Black King on e6 instead of e7 and the result changes.

The similar h pawn ending is a draw as one would expect.


Matt Fletcher said...

Could have been a blue or red pill question - obviously you don't move the pawns, but does the King go left or right?

Jonathan Rogers said...

actually I bet white could even win by playing 1 f4 too. I should think that everything wins.

JB - you can add two more king and pawn endings to your collection from the recent Barbican 2 v Wood Green match (Houska v Berry and Speelman v Coleman). You could even have three pills for the former; there were three plausible moves at one stage, one of which wins, one which draws and one which lost.

Matt Fletcher said...

@Jonathan Rogers - Surprisingly Nalimov will tell you there's only one move that wins.

1.f4 f5 only gets you a draw.

an ordinary chessplayer said...

@Matt Fletcher - thanks for the 1.f4 f5 = hint.

At first I thought it was an easy win (e.g. both 1.Kg2 and 1.Ke2), then I thought it was a draw, but with the hint I think I have it worked out. 1.Kg2? f5 2.Kg3 Kf7 3.Kf4 (3.Kh4 Kg6 4.f4 Kh6 =) Kf6 4.Ke3 Ke5 5. f4+ Kd5 6.Kd3 Kc5 7.Kc3 Kd5=. 1.Ke2 Ke6 2.Ke3 Ke5 3.f4+ Kd5 4.Kf3 f5 5.Kg2! (5.Kg3? Ke4 =) Kd4 (5...Ke4 6.Kg3) 6.Kh3 Kd3 7.Kh4 +-. Unfortunately my flag fell on Wednesday.

Matt Fletcher said...

@an ordinary chessplayer - just followed your Ke2 line through. What happens after 5.Kg2! Ke6! ?

an ordinary chessplayer said...

You have a point. So, back to my first variation, 1.Kg2 (no punctuation this time) f5 2.Kg3 Kf7 3.Kh4 Kg6 4.f4 Kh6 5.Kg3 Kg6 6.Kf3 Kf6 7.Ke3 Ke6 8.Kd4 Kd6 9.f3 +-.

1.Kg2 Kf6 2.f4 (2.Kg3 Kg5 is a mirror of 2.Ke3 Ke5) Kf5 (2...Kg6 3.Kg4 f5+ 4.Kf3) 3.Kf3 f6 4.Ke3 Ke6 5.Ke4 f5+ 6.Kd4 is the same.

If I failed again, I will just resort to the tablebase.

@JB - Do you have a source for the position?