# [Retros] About T.Orban problem; Yefim's letter 01/12/2005

Ryan M. DoubleExclam at comcast.net
Tue Jan 11 02:14:55 EST 2005

The intent of Orban is to show a paradox; there are several solutions in
3.0 moves,
yet only one way to reach the position in 4.0 moves. It does not seem
natural that
adding more moves (seemingly more possibilities) to the stipulation
should result in
less solutions. This is a great problem to show to the beginning Proof
Game solver. The move Ke7! is difficult to find, and they seem to
appreciate the paradox after they solve it.

I don't consider the loss of castling rights in this problem to be
interesting at all.
Adding it to the stipulation would only distract the solver from the
real point, which
is the tempo paradox described above. It also gives solvers a hint that
the black King might move, which ruins the Eureka factor. I don't agree
that Friedel's stipulation is
an improvement.

Regards,

Ryan McCracken

-----Original Message-----
TregerYefim at aol.com
Sent: Monday, January 10, 2005 10:17 PM
To: retros at janko.at
Subject: [Retros] About T.Orban problem; Yefim's letter 01/12/2005

Hello from Yefim T.
We all know well known problem of T.Orban. It was recently
publish in Chess Base as an example of SPG after 3 or 4 moves for the
position
rnbqkbnr/pp3ppp/2p1p3/8/4P3/8/PPPP1PPP/RNBQK1NR w
I have told Frederic Friedel about a little flaw of this problem.
If the task is to find SPG after 4 moves then we come to One position
(after
1.e4 e6 2.Bb5 Ke7 3.Bd7 c6 4.Be8 Ke8); where Black castles are lost.
If the task is to find SPG after 3 moves then we come to Another
position (after
1.e4 c6 2.Bb5 e6 3.Bc6 dc6) when Castles are save.
So, we are talking about different positions!
I agree with answer of Friedel that in composition it is allowed not to
point out such things (to make it interesting).
But I suspect that in history some speculation around this problem
occured.
In particular, at first it was said about 3 moves, after that 4 moves,
hinting on the same positions, but they are not!
Does somebody know about real intention of T.Orban? Who made up with a
speculation above?
And the improvement (Friedel): for this problem a task is in the
question: may Black still castle in this position occured after 4 moves?
P.S. This problem is not on contest so we may discuss it.
Yefim 01/12/2005