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MatPlus.Net Forum General The S#5 Excelsior
 
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(1) Posted by James Malcom [Friday, Mar 13, 2020 03:12]; edited by James Malcom [20-03-13]

The S#5 Excelsior


The excelsior in 5 moves to mate has been plenty done directmates and helpmates, but I had yet to see it in a selfmate. I did a search, but all that turned up was a s#6 that is easily converted to be 5 moves long.

Terho Marlo, Suomen Tehtäväniekat 05/2010, P1178122
s#6
(= 9+9 )


As such, I did some tasking to find the most economic positions for underpromotion excelsiors. Here is my work for the fun of it!

s#5
(= 4+4 )


s#5
(= 5+4 )



s#5
(= 3+5 )



As far as I can tell, a queen promotion can’t be done it 5 moves, but in can be easily done in a 6-move miniature.

s#6
(= 5+2 )


Who knows of an early orthodox s#5 that contains an excelsior?
 
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(2) Posted by seetharaman kalyan [Friday, Mar 13, 2020 06:19]; edited by seetharaman kalyan [20-03-13]

All these are in fact stalemates. Not sure if selfmate scheme is feasible.
 
 
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(3) Posted by Hauke Reddmann [Friday, Mar 13, 2020 10:02]; edited by Hauke Reddmann [20-03-13]

Here's an idea for Q (untested):

(= 4+6 )


I also have some vague ideas for non-stalemate
based but as an OTB player, I don't do s# (usually :-)

EDIT: "Vague idea" = "in 10 minutes I got the
problem ready, probably still gruesome cooked" :-)

(= 7+5 )

 
   
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(4) Posted by Frank Richter [Friday, Mar 13, 2020 10:25]

Seetharaman, the promotions to B and R contain selfmate motivation (avoid to attack the black battery). In a stalemate the Q-promotion would simply work too.
But generally you are right, mainly this are stalemate schemes.
 
   
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(5) Posted by Zalmen Kornin [Friday, Mar 13, 2020 10:41]

Hauke, Your first diagram is a s#4 (Rg7!). The intended solution works removing the bPh5 (still C- though)
 
   
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(6) Posted by Frank Richter [Friday, Mar 13, 2020 11:09]; edited by Frank Richter [20-03-13]

It's C+ without bPh5.
And we got a twin:
b) bKh6 (or h8) ... 5.f8S
Of course this is in fact a stalemate in 5 ...

Second diagram is s#4 with 2 solutions:
1.Be2-e3 Kd7-d8 2.Be3-e4 Kd8-d7 3.Be4-e5 Kd7-d8 4.Be5-e6 Sg7-f5/Sg7-h5/Sg7:e6/Sg7-e8# or 1.Be2-e4 etc.
 
   
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(7) Posted by Hauke Reddmann [Friday, Mar 13, 2020 11:23]

Like I said, gruesome cooked :-)
But in diagram 2, we have no stalemate motivation and
simply bPg4 instead of w should work!
 
   
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(8) Posted by Frank Richter [Friday, Mar 13, 2020 12:34]

1.- g4-g3 2.- g5-g4 3.- B~ ??
 
   
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(9) Posted by Nikola Predrag [Friday, Mar 13, 2020 13:22]

It's indicative how such a mechanical idea of 'excelsior' almost automatically turns off the human creativity and intelligence. Instead of critical thinking we are all too ready to apply mechanical procedures, happily careless about the essence.

How can Frank (post 8) 'see' 3.- B~ ??, overlooking the checks 3.e6+,4.e7+ & 5.e8Q+
or Hauke (post 3) not being aware of the intrinsic cooks in both examples
or Rewan missing s#1 with 5 solutions in his very 1st example
???
 
   
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(10) Posted by Frank Richter [Friday, Mar 13, 2020 13:47]

Yes, indeed ... very good point.
 
 
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(11) Posted by seetharaman kalyan [Friday, Mar 13, 2020 14:03]

@ Frank Ritcher.. you are right. B or R promotion indeed has selfmate motives. Like Nikola said I wrote hastily !!
 
   
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(12) Posted by James Malcom [Friday, Mar 13, 2020 16:31]; edited by James Malcom [20-03-13]

Well I never said that my examples were correct Nikola-they were just mechanical concepts.

Thanks for pointing out knight excelsior is cooked. The twin to the C+ version of Hauke’s queen excelsior shall do as the most economic form.

Also, if we want two different promotions of the same pawn, here if my offering without twins.

s#5
(= 5+7 )


If 4... Kh2, then 5. a8=B, and if 4... h2, then 5. a8=N. It’s also a Meredith!
 
   
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(13) Posted by Hauke Reddmann [Saturday, Mar 14, 2020 19:50]

@Nikola: It's teh internets, I don't check my schemes
(not problems!) that hard as e.g. for the SCHWALBE,
where merely the themes will be botched :-)
I immediately spotted after posting: Oopsie, e3.
Then I tried ten minutes in vain to add sPf7/wRg7 so that
the P is pinned until after another ten minutes I
realized it's no stalemate anyway :-)
@Rewan: Qc5 Pd5 instead of Pb5 Rc6 might save Pg6.
 
 
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MatPlus.Net Forum General The S#5 Excelsior