Saturday, May 23, 2009

White to play and win and


Study by Gurgenidze

Without further computer assistance:

(a) show how White wins ;

(b) show why the study is cooked if the White rook on g5 is moved to g6.

9 comments:

Jonathan B said...

Either I'm missing something obvious or Justin's left us a tough one here...

Anonymous said...

Well, I have worked out (a): 1. Rg1 forces the advance of either e-pawn or f-pawn, else 2. Rxe3:

1. ... f2 2. Rf1 e2 3. Rxf2+ Ke7 (3. ... Kg7 4. Rg3+ Kh6 5. Rh3#) 4. Rxe2+ Kd6 5. Rxd2;

1. ... e2 2. Rxf3+ Ke7 3. Rff1! and demonstrate your knowledge of K+R mate technique.

But I don't yet have (b). Some kind of mate using the ranks, perhaps?

Jonathan B said...

I considered 1. Rg1 too, but what about

1. ... f2, 2. Rf1 d1=Q, 3. Rxd1 e2

rather than the immediate 2. ... e2?

Now there's no Rxf2 check.

Jonathan B said...

Also,

1. Rg1 f2, 2. Rd1 e2 (not the mirror of the previous line with 2. ... f1=Q because 3. Rxf1 is check so there's no time for Blac to play ...e3-e2

Jonathan B said...

Thought I had it then (borrowing an idea from your second line)

1. Rg1 f1, 2. Rf1 d1=Q, 3. Rxd1 e2, 4. Rf3+ Kg7, 5. Rg3+ Kf6, 6. Rgg1

Black can't do anything with the pawns ... but then I thought what if he just advances the King. Can White actually take either of the pawns without losing the other rook?

Jonathan B said...

Oh of course he can...

6. ... Ke5, 7. Rge1

that does it I think.

Anonymous said...

1. Rf6+

1... Ke7 2. Rxe3+ Kxf6 3. Rxf3+ etc

1... Kg7 2. Rd6

1... Kg8 2. Ra8+ Kg7 3. Rd6 Kf7 4. Ra7+ Ke8 5. Ka2 f2 (5...e2 6. Rh6) 6.Re6+ and 7. Rh6/b6

Richard

Anonymous said...

Without further computer assistance? What computer assistance have we had up to that point? Nice puzzle btw (probably because I managed to solve it!).
Andrew

ejh said...

I'm thinking that you probably can't see the diagram without computer assistance....