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MatPlus.Net Forum General The $80 Theme
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(21) Posted by Jakob Leck [Tuesday, Jan 14, 2020 21:53]

Thanks, Kenan, I misunderstood, then. For those 90 dollars or should be relevant as well (although they do not fulfil Rewan's requirements).
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(22) Posted by seetharaman kalyan [Tuesday, Jan 14, 2020 21:54]; edited by seetharaman kalyan [20-01-14]

(= 1+4+1N )

h#1 2 solutions

Well Hauke wanted three under promotions. All three underpromotions are here, but not by same side!
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(23) Posted by Kenan Velikhanov [Wednesday, Jan 15, 2020 04:53]; edited by Kenan Velikhanov [20-01-15]

For the full implementation of the theme, pawns should be on the same vertical. Therefore, the presence of other white materials is required. This complicates and makes it impossible to reach the target.
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(24) Posted by Rewan Demontay (Real Name: James Malcom) [Wednesday, Jan 15, 2020 16:47]; edited by Rewan Demontay (Real Name: James Malcom) [20-01-15]

Kenan’s h#45 from earlier is this thread, which has no promoted pieces, is still a themeatic; $90 theme my requirement is juat an extra dose of challenge. P1111722. P0559583, and P1285917 are indeed relevant to th $90 theme. I did a search and turned up YAC 406363 as well:

To Kenan-I assume you mean that th $90 theme with my requirement cannot be done with promoted peces? For a demonstration with promoted pieces, it is possbile to take a well known scheme(P1077165) and whittle off a half-move for a fully themeatic $90 theme.

h#4.5-Not Mine
(= 6+13 )

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(25) Posted by Kenan Velikhanov [Wednesday, Jan 15, 2020 18:08]; edited by Kenan Velikhanov [20-01-15]

Dear Rewan, the theme of 80-90 dollars should be taken as a joke. This is not the first and not the only feasible theme. There are other well-known thems that can be implemented in full. The Russians have such a proverb “hope dies last”, so that not everything is still lost, we will still try to please our colleague.
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(26) Posted by seetharaman kalyan [Wednesday, Jan 15, 2020 19:07]

Rewan, any long-mover can be shortened by omitting the first few moves.
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(27) Posted by Rewan Demontay (Real Name: James Malcom) [Wednesday, Jan 15, 2020 19:58]; edited by Rewan Demontay (Real Name: James Malcom) [20-01-15]

To Kenan-I know it’s a joke since I started the joke here. But perhaps I am taking it a bit too seriously...or am I? :)

To seetharaman-Well of course it’s possbile. I just did it!
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(28) Posted by Joaquim Crusats [Wednesday, Jan 15, 2020 20:43]

Is this a correct 90$ (joke) with "the requirement"?

(= 9+12 )

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(29) Posted by Rewan Demontay (Real Name: James Malcom) [Wednesday, Jan 15, 2020 21:08]; edited by Rewan Demontay (Real Name: James Malcom) [20-01-15]

It is indeed correct-tested with the Helpmate Analyzer:

Nice (joke) work Joaquim!
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(30) Posted by Nikola Predrag [Thursday, Jan 16, 2020 18:05]

Rewan, the only really interesting question is about motivating the black double step in h#5. Without that = 0$.
Black tempo-promotion is a well known tool.
h#4.5 might have some constructional value (for instance, as a meredith).
5+8 is possible, now there's a challenge for you.

(= 5+8 )
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(31) Posted by seetharaman kalyan [Thursday, Jan 16, 2020 22:08]; edited by seetharaman kalyan [20-01-16]

@Nikola. I think Tempo promotion is only tool discovered for black so far.
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(32) Posted by Nikola Predrag [Thursday, Jan 16, 2020 22:43]

It was discovered long ago as a possible tool for 100$ task, but the thematic bP might loose tempo in the 1st of 5 moves.
So, an ORIGINAL idea would be interesting instead of re-presenting the old one's weakness.
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(33) Posted by Andrew Buchanan [Saturday, Jan 18, 2020 13:14]; edited by Andrew Buchanan [20-01-18]

The area round the famous $100 Theme is much trodden, will frequent duplication and near duplication, particularly involving reflection. I thought it would be helpful to clear up the history in PDB so one can see the best example of each matrix. To see for yourself, go to PDB and ask:
k='100' and not g='fairies' and cplus and not k='anticipated' and not k='superseded' and stip='h#5'

There are basically just 4 matrices, with the best example of each being:
P0559554 Ban 1965 +LLLsss (Motivation 1)
P0559557 Rinder 1969 +Lll (and an obtrusive l too!) (Motivation 2)
P1077165 Preinfalk 2004 +ll (Motivation 1)
P1095234 Ettner/Nojek/Keym 2005 +Ls (Motivation 3)

The latter two are obviously the nearest to achieving the theme, but the other two are interesting and perhaps improvable. If PDB is missing any relevant compositions, please let me know here in Matplus.

There are 3 motivations for the initial double pawn move by Black:
(1) Avoiding blocking advancing wP on same file.
(2) Avoiding checking wK on 5th rank.
(3) Capture wP on 2nd rank, which is blocking wB, and then move off.

What other motivations might there be in principle?
(4) Capture wP on 2nd rank, which is blocking wR, and then move off. [Having a wR seems dangerous from soundness perspective.]
(5) Pawn advances simply to spend 5 tempos, and cannot end up on 2nd rank because it would block Wh line unit. [This forces the position to allow no casual Bl switchbacks, which seems difficult to ensure.]
So I don't think either of these is practical. Any other ideas?

One other unexplored possibility is a $95 Theme, which would be a full h#5, but with the Bl pawn beginning on 6th rank - with the 7th rank square empty as a courtesy to Rewan's sensitive aesthetic nature :-)
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(34) Posted by Rewan Demontay (Real Name: James Malcom) [Saturday, Jan 18, 2020 20:50]; edited by Rewan Demontay (Real Name: James Malcom) [20-01-18]

You are correct Nikola. that it does have constructional value. However. I think your 13-piece $90 theme is the most economical that is can get.

To Andrew-Werner Keym pretty much covered the basic history as you did. along with known and shown motivations, of the $100 in Die Schwalbe 2005: (the only wrinkle is that diagram F was completely anticipated by P1077165).

Those are indeed interesting, unimplemed motivations though. I’ll play around with them-in illegal positions of course.

The $95 theme has been done (see Jakob message on the top) but with the 7th rank full. I’ll try to make it cleared as you suggested. :)
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MatPlus.Net Forum General The $80 Theme