test position from rybka board

[yanquis1972]

this is continuing a variation of a position posted at the rybka forum --

[d]n1QBq1k1/5p1p/5KP1/p7/8/8/8/8 w - -[/d]

Bc7!! wins outright. as soon as u input this into any engine w/in a second the ones ive tried will see that it mates.

how quickly do engines see this, without demonstration? do they play it at all or is it just pruned away?

[George Tsavdaris]

this is continuing a variation of a position posted at the rybka forum --

[d]n1QBq1k1/5p1p/5KP1/p7/8/8/8/8 w - -[/d]

Bc7!! wins outright. as soon as u input this into any engine w/in a second the ones ive tried will see that it mates.

how quickly do engines see this, without demonstration? do they play it at all or is it just pruned away?

This position arises almost every year in CCC.

See here:
2008
2004
2003
etc.....

[BBauer]

Yeah, this position occurs again and again!
Why?
Perhaps because it is not solved?
I wish this position will come up again and again - until it is solved.

kind regards
Bernhard

[Vinvin]

It's matter of depth and selectivity !
The first moves seems very bad and so are prunned ... the depth to see they are good is very big. The engines will see it's winning if you let it ponder very long (or if you use a very very fast computer).

[BBauer]

How long?
regards
Bernhard

[Vinvin]

Nobody knows until one let it run long enough ...

How long?
regards
Bernhard

[BBauer]

So you cannot say
"It's matter of depth and selectivity !"

It may very well be *never*

kind regards
Bernhard

[tano-urayoan]

It's matter of depth and selectivity !
The first moves seems very bad and so are prunned ... the depth to see they are good is very big. The engines will see it's winning if you let it ponder very long (or if you use a very very fast computer).

Wrong this position is about zugzwang, engines are no good at it so that is the trick of the position. Zappa has solved this position after not enabling null move.