PG in 21.0

BigDoggProblem
Posers and Puzzles 10 Dec '05 06:47
1. BigDoggProblem
Court Jester
10 Dec '05 06:471 edit

Proof Game in 21.0 moves
(Position after Black's 21st move. How did the game go?)
2. 10 Dec '05 08:51
This is going to be interesting: I can count 5 king moves, two bishop, 8 knight, 6 pawn for a total of 21 moves on White's part. But that leaves no moves for the capture of Black's "a"-pawn. Back to the drawing board ðŸ˜‰.
3. 10 Dec '05 09:06
It's easy enough to work out how to get to that position in 23.0 moves. But then it wouldn't be much of a problem then would it.

Thus far (as I can see):

Only two captures made and both by white. The bishop on f8 (which must be by a knight - min 8 moves) and the a-pawn, which must have been captured on its own file.

White pawns have made a minimum of 6 pawn moves and five to get the king to his current position (either all to the king or six with the queen sidestepping out of the way). The black squared bishop has made at least two moves.

And I've now made 21 moves.

Can't cut down on the bishop or pawn moves. Can't see a way for king or g-knight to reduce theirs either.
4. 10 Dec '05 16:57
I don't have the time this weekend to look in the details of how and in what sequence, but given that black has 19 spare moves, and counting moves for white, it should be possible that black brings out the bishop, queen and king (perhaps also the knight) and let white go with the queen and capture the f-bishop, as well as the a-pawn.

white moves:
3 h-pawn
3 other pawns
2.white squared bishop
4 king
leaves 9 moves for the queen, 4 'direct' path between d1 and f8 and 5 with the 'detour' to capture the a-pawn
5. BigDoggProblem
Court Jester
13 Dec '05 17:41
So far, the piece that captures the bishop has not been mentioned.
6. 13 Dec '05 18:15
Well as the queen and kings knight have been mentioned. The queens knight won't save time that I can see, too far for the king, so that must make it the rook on h1.
7. 13 Dec '05 19:19
Originally posted by Peakite
Well as the queen and kings knight have been mentioned. The queens knight won't save time that I can see, too far for the king, so that must make it the rook on h1.
How can anything but the king's knight capture the bishop? Pawns don't move backwards do they?
8. 13 Dec '05 20:17
No, but rooks move forwards, sideways and backwards.
9. 13 Dec '05 20:50
Originally posted by Peakite
No, but rooks move forwards, sideways and backwards.
It was rhetorical.
10. 13 Dec '05 23:19
Originally posted by BigDoggProblem
So far, the piece that captures the bishop has not been mentioned.
If I reread my previous post correctly, then the white queen would have taken the bishop, no?
11. BigDoggProblem
Court Jester
14 Dec '05 00:21
Originally posted by Mephisto2
If I reread my previous post correctly, then the white queen would have taken the bishop, no?
No, because you mentioned the Queen.
12. 14 Dec '05 00:36
Originally posted by BigDoggProblem
No, because you mentioned the Queen.
"............... and let white go with the queen and capture the f-bishop, as well as the a-pawn.
"
13. BigDoggProblem
Court Jester
14 Dec '05 02:00
Originally posted by Mephisto2
"............... and let white go with the queen and capture the f-bishop, as well as the a-pawn.
"
People had conjectured which piece takes the Bishop, but nobody had guessed the correct piece at the time I posted the hint (5th post in thread).
14. 14 Dec '05 20:16
Originally posted by BigDoggProblem
People had conjectured which piece takes the Bishop, but nobody had guessed the correct piece at the time I posted the hint (5th post in thread).
It works easily if black doesn't even start with a bishop.

Perhaps, the player just took it off the board, or they agreed to the handicap?
15. 14 Dec '05 20:571 edit
Originally posted by Tetsujin
It works easily if black doesn't even start with a bishop.

Perhaps, the player just took it off the board, or they agreed to the handicap?
This isn't a Bowmann problem.

Been trying a few ways of getting this done.

White moves 6P, 5K, 2B leaving 8 for the rook.
So it can go from h1 to h4/h5 (not sure which but leaning towards h5), then to a4/a5, a8 and f8 before returning. Which is all of his accounted for.

So black has a minimum of three pawn moves (to b4 and a5), the rest to shuttle his pieces out and back again. So max of 18 to do this, or 9 each way. K min 3, Q min 2, so four for B,N,R. Because the rook can't get past the a-pawn, he must move twice, so the B is only allowed one move (to a6 - the K must take b7), ditto the N to c6.

And my big problem at the moment is that I think the b pawn must get to b4 before the black pieces can move out, however this blocks the white K through c3, so can't take place before the 5th move. K to c3, pawns to e3/b3. a5, b5, Nc6 and Rb8 needed first