1 problem(s) found in 1242 milliseconds (displaying 1 problem(s)). [PROBID='P0008506'] [download as LaTeX]

1 - P0008506
Valery Liskovets
R45 Rex Multiplex 15-16 1986

(7+9)
#2
a) RS (PF)
b) pRA
pièces retro-volages

"Retro-volages" assumes every chessman (or a maximal possible set of them) to be volage, i. e. betrayable (capable to become an enemy). This is assumed, unless the opposite have been proven for all proof games. Every volage chessman (except for King) necessarily changes its color when it moves to a square of the opposite color for the first time. After that it remains a normal (unrecolorable) chessman. Both black dark-squared Rooks on even ranks cannot be volage simultaneously: even if one of them were a promotee, it had to visit a square of the opposite color at least once in order to arrive from the first rank! a) The PF (subordination) logic assumes the first moving man changing the color of its square to be volage. An autocheck by a recolored man is illegal! 1. Re4 (zugzwang) fxe4 2. Rxc4#!! A Buridan-ass situation: no bl R can help (2. ... Rb4=wT??) in spite that one of them is undoubtedly a normal one (but which one is unknown)! b) By the pR=A logic, W may know the volage chessman in advance. I (Rb6 is volage) 1. Ra8 R4- 2. Bb8#! (2. ... Ra6=wT??) II (Rb4 is volage) 1. Rg1 R6- 2. Ra1#! (2. ... Ra4=wT??)

comment

Keywords: Retro-volages, Post Factum (PF)
Genre: Retro, 2#, Fairies
FEN: 4R3/BpN5/1rp5/k1p2pR1/1rp2P2/1pK5/1N6/8
Input: Gerd Wilts, 1996-12-14
Last update: A.Buchanan, 2023-06-03 more...

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