[Retros] Accidental retro

[Noam Elkies]

"Mario Richter" <mri_two at t-online.de> writes:


>> ... Does the book mention the retroanalytic content in the

>> solutions section?  For that matter, what does it give as

>> the solution of #2940?



> The solutions presented in one of the appendices of the book

> are of the following format:

> Name, year, keymove.

> No mentioning of threats, set-plays or retroanalytical content.



> For #2940 it gives:

> L. Szász, 1927, 1.Ne7



> This surely refers to the hungarian composer Dr. Lajos Szász (1906-1929).


1906-29 -- died at 23!?


> Interestingly, he has composed some retro-problems too, eg.

> www.softdecc.de/pdb/search.pdb?expression=PROBID='P1012852'

> or

> www.softdecc.de/pdb/search.pdb?expression=PROBID='P1012848'



> so the retroanalytical content in #2940 might well have been intentional.


Thanks for checking on this.  Given the treatment of other retros
that you noted in Polgar's book, you're probably right to suggest
that the problem was intended as a retro by its composer.
It would be nice if the book also listed sources for
the various positions so that one could check the original.


> I used the orthodox mate-in-n problems of that book

> as a test suite for my own little solving program.



> So after I received your posting on the retros mailing list,

> I looked what my program had said about this problem.

> And its verdict was: "Illegal position. Black has no last move."


I wasn't aware that computer programs can now check this.
Is yours the first such program?  Does it also recognize
illegality of Castling in #1747 or #1942?


> P.S.: One nice problem of L.Szász is the following two-mover:



> W: Kc7 Rh7 Re3 Bg8 Nh4 Pe2 Pf7 Pf4

> B: Ke7 Be4 Pf5


Yes, it's nice, thanks -- I don't recall seeing this motivation before.

NDE