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Subject: Re: How many positions in 4 or 5 piece endgames?

Author: José de Jesús García Ruvalcaba

Date: 10:17:12 10/13/98

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On October 13, 1998 at 13:04:17, Ernst A. Heinz wrote:

>On October 13, 1998 at 12:23:29, John Coffey wrote:
>>
>>How many possible positions are there in all 4 or 5 piece endgames?
>>I am thinking that it must be between billions and trillions.
>>do such endgames take advantage of symetry?
>
>If you do not discount illegal positions there are 64^X possible constellations
>of X pieces. By removing symmetries, not placing more than one piece on the same
>square, and not placing the Kings directly beside each other, you can easily
>reduce this number to:
>
>  (a)   462 * 62 * 61        for 4-piece endgames without Pawns,
>  (b)  3612 * 24 * 62        for 4-piece endgames with a single Pawn,
>  (c)  3612 * 24 * 47        for 4-piece endgames with 2 Pawns (no en-passant),
>
>  (d)   462 * 62 * 61 * 60   for 5-piece endgames without Pawns,
>  (e)  3612 * 24 * 62 * 61   for 5-piece endgames with a single Pawn,
>  (f)  3612 * 24 * 47 * 62   for 5-piece endgames with 2 Pawns (no en-passant),
>  (g)  3612 * 24 * 47 * 46   for 5-piece endgames with 3 Pawns (no en-passant).
>
>I have submitted an article to the ICCA Journal which describes the according
>index schemes among other things.
>
>=Ernst=

That gives a grand total of 1167385380 (please check, I could have mistyped).
How many more position are added by taking in account en-passant?



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