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## #1 2015-03-23 21:35:17

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,608

### Mate in 15...or less?

Hi;

I saw this on another forum, from a 2012 thread. The shortest solution found there was mate in 15, using these chess engines: Critter 1.4, Stockfish 2.2.2 (both freeware) and Houdini 2.0c (commercial).

White's pawns move up, Black's down, and White moves first.

Without analysing the position at all I entered it into some freeware chess engines I have, seven of which found mate in much less than 15 moves:

Engine         |          Time
------------------|-----------------
Houdini 1.5a     |      0.08 seconds
Critter 1.6a       |      1.36 seconds
Fire 4.0            |      8.44 seconds
Stockfish 6       |      9.94 seconds
Gull 3               |    15.21 seconds
Komodo 5.1r2   |    31.71 seconds
Rybka 2.3.2a    |  273.63 seconds

A couple of others didn't find mate in any number of moves after about 5 minutes (which I thought was long enough for them to think), and so I put them out of their misery.

I now regret not trying to solve the puzzle myself, because, looking at it again (with the benefit of hindsight, I know), I'm sure that a human solution for mate in much less than 15 moves isn't all that hard to find.

So, the challenge I'd like to set is for you to solve for mate in 'much less than 15 moves'...but without any chess engine help.

Please hide your answer, in which I'd like you to include the moves line (I think there's only one optimum line) and your reasoning.

Last edited by phrontister (2017-02-27 11:25:15)

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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## #2 2015-03-23 23:54:07

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,039

### Re: Mate in 15...or less?

Are you sure it's not white down black up. Cause if it's what you said, Black is already mated.

Last edited by anonimnystefy (2015-03-23 23:56:23)

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #3 2015-03-24 00:02:57

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,608

### Re: Mate in 15...or less?

But Black is not in check yet...

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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## #4 2015-03-24 03:36:40

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,039

### Re: Mate in 15...or less?

Was "White up" referring to the direction White's pawn are moving or the part of the board White's pieces occupy at the beginning?

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #5 2015-03-24 10:12:58

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,608

### Re: Mate in 15...or less?

Sorry about the confusion, stefy...I've fixed the wording.

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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## #6 2015-03-24 11:44:30

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,039

### Re: Mate in 15...or less?

Thanks!

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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