  No.586 Nicolas Dupont (France) |
Original Problems, Julia’s Fairies – 2014 (II): May – August →Previous ; →Next ; →List 2014(II) Please send your original fairy problems to: julia@juliasfairies.com |
No.586 by Nicolas Dupont & Paul Rãican – This time Back-to-Back condition is used in PG problem! Authors main idea was a construction of Schnoebelen Queens. (JV)
Definitions:
Back-To-Back: When pieces of opposite colors stand back-to-back with each other on the same file (white piece is on the top of black!), they exchange their roles. A pawn on the first rank cannot move. Any piece can make an en passant capture when it has got a role of Pawn by Back-To-Back.
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No.586 Nicolas Dupont & Paul Rãican |
Solution: (click to show/hide) |
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white Bf1c1 Ke1 Qd1 Ph2g2f2e2d2c2b2a2 Sg1b1 Rh1a1
black Bf8c8 Ke8 Qd8 Ph7g7f7e7d7c7b7a7 Sg8b8 Rh8a8
PG8,5 (15+15) |
In my opinion, the presence of two light-squared Bishops for each side is not a flaw. This would be annoying in an orthodox proof game, because one of them would have to be promoted, but with Back-to-Back, it is not the case. Let’s call it a slight inconvenience, because it gives away that at some point, the Bishops moved using Back-to-Back support, but I would not criticize the problem because of that.
Schnoebelen is a difficult theme in orthodox proof games, but not as much when fairy conditions are involved. Here, there are nice fairy effects to achieve the intended thematic content very economically.
Is there a specific example showing that Popeye 4.69 still has bugs with the Back-to-Back condition? I can imagine it is unable to test this problem in a limited time, but I hope not because of bugs.
7.b2-d4 should be specified.
Simple and clever motivations for Q-promotions.
As far as I can see, Popeye doesn’t accept a Back-to-Back sequence where a visible unit moved in a fairy way. As an example the 3.5 skeleton is not detected (but is with WinChloe).
I asked Julia if it is possible to detail the Back-to-Back moves in the solution, e.g. 4.h6-g8=Q. But I don’t know if it is feasible, maybe the animated solution is working only with 4.h8=Q.
Popeye has bugs when I tried to add the combine Kobulking & Backtoback. Example: white Kd7 black Sf5 Ka8 H#2. Popeye gives no solution, though the solution is 1. Sd6+ Kb6 2.Sb7 Kxb7#
For now Py2Web doesn’t allow to detail moves in the solution, but I’ve added the detailed solution as a comment for now. I hope it will help! (1.h2-h4 f7-f5 2.h4-h5 Sg8-f6 3.h5-h6 Sf6-h5 4.h6-g8=Q! g7-c3 5.Sb1-a3 Bf8-g7 6.Sa3-c4 c3-b1=Q! 8.Bc1-b2 Sh5-g7 9.Bb2*b1)
Kudos for showing a the theme impossible without fairy conditions !
Kudos for showing a theme impossible without fairy conditions !
Now, Jacobi is able to check this PG. Tested with 7.Pb2-f6 in about 2000sec.