Mate in 3? Or is it mate in 4?

[Rick Garel]

Is anyone familiar with this problem? A friend of mine gave it to me and said it was a mate in 3. I couldn't find the mate in three, so I passed it on to the 'silicon monster' (Rybka 3) and it found a mate in 4. So who is right, my friend or Rybka?

[Kerry Liles]

Re: Mate in 3? Or is it mate in 4?

Is anyone familiar with this problem? A friend of mine gave it to me and said it was a mate in 3. I couldn't find the mate in three, so I passed it on to the 'silicon monster' (Rybka 3) and it found a mate in 4. So who is right, my friend or Rybka?

My money is on Rybka... unless your friend is Kasparov.

[Rick Garel]

Re: Mate in 3? Or is it mate in 4?

You are probably right. I'm just covering my bases before I go back to my friend and tell him he was wrong.

[Egidijus Zeromskis]

Re: Mate in 3? Or is it mate in 4?

My money is on Rybka... unless your friend is Kasparov.

Rybka might find the easiest possible mate, but not necessary the shortest.

I would try with a Mate engine. (It is included with Fritz.)

---

Other software gave a mate within 3 moves ;)

---

and the short search

BAIRD, W.j. Mrs.
Manchester Weekly Times, 1893
1st Prize

[Kerry Liles]

Re: Mate in 3? Or is it mate in 4?

Rybka might find the easiest possible mate, but not necessary the shortest.

I would try with a Mate engine. (It is included with Fritz.)

---

Other software gave a mate within 3 moves ;)

---

and the short search

BAIRD, W.j. Mrs.
Manchester Weekly Times, 1893
1st Prize

Great work! Now I will have to work on the mate in 3 for real... thanks!

[Jean Deschesnes]

Re : Mate in 3? Or is it mate in 4?

Qb8 mate in 3 in all variations .

[Peter Bokhout]

Re: Re : Mate in 3? Or is it mate in 4?

Qb8 mate in 3 in all variations .

If 1.Qb8 what does White do after 1....Ke6?

If the white pawn were on h2 instead of h3, then 1.Qc8 is a solution. For example, 1.Qc8 Kd6 2.Bb5 Kd5 3.Qc6++, or 1.....Ke4 2.Qe6 Kf3 3.Qe2++.

[Hugh Brodie]

Re: Mate in 3? Or is it mate in 4?

1. Qb8 Ke6
2. Bc4+

2.....Kf5 3. Qb1++
2.....Kd7 3. Ne5++

[Paul Bonham]

Re: Mate in 3? Or is it mate in 4?

Is anyone familiar with this problem? A friend of mine gave it to me and said it was a mate in 3. I couldn't find the mate in three, so I passed it on to the 'silicon monster' (Rybka 3) and it found a mate in 4. So who is right, my friend or Rybka?

Are you serious that Rybka didn't find the 3 move mate? The engine that comes with Scid, TOGA (not even the latest version) found the 3 move mate immediately (i.e. under 1 second).

Perhaps you've found a hole in Rybka?

[Egidijus Zeromskis]

Re: Mate in 3? Or is it mate in 4?

Are you serious that Rybka didn't find the 3 move mate? The engine that comes with Scid, TOGA (not even the latest version) found the 3 move mate immediately (i.e. under 1 second).

Perhaps you've found a hole in Rybka?

Just tested with Fritz and Rybka, both find mate in 4, and both engines stopped :) Some clicking forces them to search again and to find mate in 3 ;) Nothing new.