18.0 moves.
Interestingly, each side can theoretically reach their own position in 17 moves, but all the interferences between the pieces make this practically impossible.
The many interferences were my main strategy for boosting the move count. My hope is that I can turn this position into a unique captureless proof game where every piece moves at least once.
The extension is cooked though. The bQ can go directly to a5, allowing for several SPGs in 23.5.
How about if the c-pawn doesn't move? (#6813)
Here are two SPGs in 22.5 found by Stelvio 2.1 for this one.
Here are two SPGs in 22.5 found by Stelvio 2.1 for this one.
It's proving tricky to try and get the black rooks involved.
It's proving tricky to try and get the black rooks involved. (#6815)
SPGs in 21.5.
How short a proof game can you find for this position, inspired by one seen in the Illegal Position thread?
@6818
Huh
How short a proof game can you find for this position, inspired by one seen in the Illegal Position thread? (#6817)
Here's the 36-move proof game I made just to have a legal game ready to show. How much shorter can you make it?
@6820
Shorter:
Chat's been a little inactive recently.
How about a challenge: What's the fastest game you can find where white moves a knight to every square on the 7th rank, and black moves a knight to every square on the 2nd rank?
And an even more specific bonus: Without the knights capturing anything.
Starting from the initial array, how fast can you reach a position with White to move in which any of 15 white units can move to the same square? I looked at this a little bit and made a 62-move game that works. How much faster can it be done?
@6825
Shorter:
@6826
55
Starting from a legal position, here's one way this position could have been reached.
@6826
55
Very nice, good improvement on my first try.
The extension is cooked though. The bQ can go directly to a5, allowing for several SPGs in 23.5.
How about if the c-pawn doesn't move?