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From: humbert@ihuxj.UUCP (humbert)
Newsgroups: net.chess,net.math.symbolic
Subject: Re: interesting (practical?) chess problem (partial spoiler)
Message-ID: <686@ihuxj.UUCP>
Date: Wed, 12-Sep-84 10:12:24 EDT
Article-I.D.: ihuxj.686
Posted: Wed Sep 12 10:12:24 1984
Date-Received: Fri, 14-Sep-84 06:43:40 EDT
References: <441@rocksvax.UUCP>
Organization: AT&T Bell Labs, Naperville, IL
Lines: 17

Problem: King and 2 Bishops vs. King; superior side cannot force mate.

Place the lone King on QR8.  Place the other King on QB7, one bishop on QR7,
and the opposite-colored bishop anywhere you like (except on the QR8-KR1
diagonal, of course).  The superior side, to move, cannot force mate.

If the bishop on QR7 moves, the lone King is stalemated.  If the King moves
from QB7 to QN6, the lone King is stalemated.  Any other move allows K x B as a
reply, reducing the superior force to King and 1 Bishop vs. King, which is
insufficient force to establish a checkmate position.

The practicality of the problem is reduced somewhat by the fact that the above
position could never occur in a real game.

Please correct me if this posting contains an error.

					jfs