Extremely difficult PG

This one is for the hardcore proof game solvers. This is one of the toughest I have solved.


PG in 21.0 moves

Originally posted by SwissGambit
This one is for the hardcore proof game solvers. This is one of the toughest I have solved.

[fen]1n2k1nr/1ppb1pp1/4p2r/3p4/3b4/8/1PPPPPPP/q3K3 w k - 0 22[/fen]
PG in 21.0 moves

????? where is bishop f1

It must be N-f1 N-e4 N-g3 Nxf1 N-g3 N-e4 N f6 N-g8

It must be N-f1 N-e4 N-g3 Nxf1 N-g3 N-e4 N f6 N-g8

No.

Originally posted by Jirakon
It must be N-f1 N-e4 N-g3 Nxf1 N-g3 N-e4 N f6 N-g8

No.

No?
Then it must be
WHITE: K-d1 K-c1 K-b1 K-a2 k-b3
BLACK: Q-a1 Qxf1 Qxh1 Q-a1 Q-a5 Q- b5
White: K-a2 K-b3 etc.

Then it must be
WHITE: K-d1 K-c1 K-b1 K-a2 k-b3
BLACK: Q-a1 Qxf1 Qxh1 Q-a1 Q-a5 Q- b5
White: K-a2 K-b3 etc.

No.

By the way, when I say "No", I don't mean that's not how it's done, I just mean, with a superficial look, one can't determine that it's definitely the method.

Originally posted by SwissGambit
This one is for the hardcore proof game solvers. This is one of the toughest I have solved.

[fen]1n2k1nr/1ppb1pp1/4p2r/3p4/3b4/8/1PPPPPPP/q3K3 w k - 0 22[/fen]
PG in 21.0 moves

What constitutes a proof game? Excuse my ignorance.

Originally posted by Zweite
What constitutes a proof game? Excuse my ignorance.

A proof game means that you are to construct a legal game ending in the diagram position. The "21.0" part means that the position should occur after 21 moves by both sides [in other words, after Black's 21st move].

The moves need only be legal, and White and Black move cooperatively with the sole goal of reaching the specified position.

"PG in 19.5 moves" would mean that White makes 20 moves and Black 19 to reach the diagrammed position.

Originally posted by SwissGambit
A proof game means that you are to construct a legal game ending in the diagram position. The "21.0" part means that the position should occur after 21 moves by both sides [in other words, after Black's 21st move].

The moves need only be legal, and White and Black move cooperatively with the sole goal of reaching the specified position.

"PG in 19.5 moves" would mean that White makes 20 moves and Black 19 to reach the diagrammed position.

Thanks for the clarification... I'll try this one, but maybe I should start with something more basic like:

Proof game in 0.5
😉

Originally posted by Jirakon
Then it must be
WHITE: K-d1 K-c1 K-b1 K-a2 k-b3
BLACK: Q-a1 Qxf1 Qxh1 Q-a1 Q-a5 Q- b5
White: K-a2 K-b3 etc.

No.

By the way, when I say "No", I don't mean that's not how it's done, I just mean, with a superficial look, one can't determine that it's definitely the method.

So if you say 'no', you mean that it could be but that there is another possibility.

Originally posted by Thomaster
So if you say 'no', you mean that it could be but that there is another possibility.

by no he meant that you cant just say that each piece must move in a certain pattern, sometimes there are multiple variations to come to the same position but until you "prove" the entire game you can not always be certain which is the correct variation....

Right Jirakon? 😉

Indeed.

I got 22.0 (in many ways). Still trying to find a way to save a move.

You may want to know that the composer original version was cooked (the Rh6 was on g6). Maybe you are interested in cooking that version...

Originally posted by David113
You may want to know that the composer original version was cooked (the Rh6 was on g6). Maybe you are interested in cooking that version...

Been there. Done that. Bought the t-shirt. [Can't think of any more cheesy cliches.]

Originally posted by Jirakon
Indeed.

I got 22.0 (in many ways). Still trying to find a way to save a move.

well you are a heck of a lot close to a solution than I ever will be. I could never solve anything like this. 😛

Is a computer able to solve this problem?