[Retros] shortest proofgames of castling switchback
elkies at math.harvard.edu
Wed Jul 18 10:36:51 EDT 2007
"Mario Richter" <mri_two at t-online.de> writes:
> Joost wrote:
>> C+ for the first 17 moves. But white just has too many free moves,
>> I don't think it can be fully computertested.
> It can be done (takes btw less than 3 seconds computer time - but
> in the approach used, some minutes have to be added for
> preparing the computer input ), but not with the current
> versions of "Natch" and Co.
> And yes - the verdict of my program was "Found one solution".
Whew. Thanks! Which program did you use?
So this row of H.Onoda's table is no longer "vacant". Still, perhaps
I gave up too late on the 19.0 move version: with 7 Bf4 no longer used
for Bh2,g3 etc. we can try to put this Bishop on g5 to stop ...Kf6
(and while I'm at it also to help restrict the bK's wife):
1 a4 g6 2 Ra3 Bg7 3 Rh3 Be5 4 d3 Nf6 5 Qd2 0-0 6 Qh6 Kh8
7 Bg5 Rg8 8 Qf8 b6 9 Rh6 Ba6 10 h4 Qc8 11 Rh3 Qb7 12 Re3 Qf3
13 Nh3 Qh5 14 g4 Bb5 15 Bg2 Na6 16 Qb8 Kg7 17 Bb7 Rh8 18 Bc8 Kf8
19 b3 Ke8
r Q B . k . . r hg-19.0
p . p p p p . p
n p . . . n p R
. b . . b . B q
P . . . . . P P
. P . P R . . N
. . P . P P . .
. N . . K . . . 16+16
I also retain the option of changing 19 b3 to 19 Kf1.
--Noam D. Elkies
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