[Retros] 2440 dead positions with moving Knight Yefim 08/28/2004
TregerYefim at aol.com
TregerYefim at aol.com
Sun Aug 29 09:41:14 EDT 2004
Hello! from Yefim.
I suspect that for technical reasons nobody received this e-mail, so, I
(with the latest questions and answers about long chess game).
For all of us: do not confuse (mix) a position and a game! Michael asks about
WKBN against Bk where a little number of moves is left for White before 50
move draw rule arises and thinks that it is not the same position as would be if
Grossmaster played. Here is a simple illustration.
Let's attribute to any concrete position number 5. What is difference between
5 (as a number) in sequences:
1 2 3 4 5 6 7 8 … and
1 2 23 24 5 6 7 8 or in
1 2 23 24 25 26 27 28…(40 times) 5 6 7 8…
There is no difference, it is the same 5, sequences are not the same! You
(retro composers) use additional (game!) information for their problems
referring to position, but have in mind that you overload a notion of position by this
information because it concerns mostly only a game (unless you use a
contradiction between "number in general" and "number in specific circumstances…" :).
Now, Math says that any two sequences are different if at least one element
of them is different, so games here are different, in my model your example
shows the difference of games, not positions.
Thank you (personally to Ryen McCracken) for the found position with
moving Knight (eternally dead position, no two draw rules).
Here it is in FEN and Alg-notation.
5b1k/4p1p1/1p2P1P1/1Pp2p2/2P2p2/2PK1p2/2PP1P2/1N6 w - - 0 1
White: Kd3, Nb1, pp:b5,c2,c3,c4,d2,e6,f2,g6
Black: Kg8, Bf8, pp:b6,c5,e7,f3,f4,f5,g7 W to move.
I will definitely use this in my book (it illustrates cyclic group with four
positions possessing of surprising property: from any of them one cannot pass
to any final position).
I have constructed the following dead set of positions with moving Knight
and the mentioned property but I am not completely sure about its legacy. So,
please check it (it has 4 White Bishops).
4k3/8/1b7/4p1p1/3pP1P1/2pP1BRB/2PpB1P1/3K1B1N w - -0 1
White: Kd1, Rg3, Be2, Bf1, Bf3, Bh3, Nh1, pp:c2,d3,e4,g2,g4
Black: Ke8, Bb6, pp:c3,d2,d3,e5,g5 White to move.
If this position is legal then 2440 positions are dead!
Bye, Yefim 08/27/2004
Last questions from Mario about games were, in particular:
(1) What is the longest possible chess game, if both sides only
move their knights and the 50-move-rule applies?
My answer is 99*27=2673 half-moves
(2) What is the longest possible chess game, if both sides only
make pawn moves?
My answer is 96.
Bye again. 08/29/2004 Yefim
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