No.936 (GE)

 No.936 Georgy Evseev(Russia) Original Problems, Julia’s Fairies – 2015 (II): July – December →Previous ; →Next ; →List 2015(II) Please send your original fairy problems to: julia@juliasfairies.com

No.936 by Georgy Evseev – Cycle in a Disparate #3. (JV)

Definitions:

Disparate PY: If one side makes a move with a piece of type “x” (black, white, neutral, half-neutral, etc., King included), the other side cannot answer immediately by moving a piece of the same type “x”. (For example: white Qc1, black Ka8,Qa7 – mate in 1 move. After 1.Qc8#, Black is mated because 1…Qb8? is illegal. The mate is possible also with the neutral nQc1 – after 1.nQc8#. Black cannot move the same neutral Queen.) Every Pawn’s promotion is a Pawn’s move, therefore after such promotion (into any possible piece) the other side cannot answer immediately with its Pawn. We can say that after the move of the figure of type “x” any enemy figure of type “x” falls under Half-moving paralysis. This paralysis disappears immediately on the next half-move, if the opponent plays with another piece of type “y”. (“Disparate PY” is implemented as “Disparate” till the latest version of Popeye, PY 4.73. In WinChloe this version of Disparate is available starting version 3.32.)

 No.936 Georgy EvseevRussiaoriginal – 19.10.2015 Solutions: (click to show/hide) White Kc7 Qa7 Rb6 Rc5 Bc1 Bc4 Sb3 Sa1 Pb5 Pd5 Pa5 Pc3 Pd3 Pe2 Black Ka4 Rf3 Bh4 Sh1 Pe7 Pg5 Pf4 Pe3 Ph3 Pf2 #3                                           (14+10)Disparate PY 1.d3-d4 ! {zugzwang.} 1...Sh1-g3 2.Bc4-d3 threat: 3.Rc5-c4 # 1...Rf3-g3 2.Sb3-d2 threat: 3.Bc4-b3 # 1...Bh4-g3 2.Rc5-c6 threat: 3.Sb3-c5 # { (C+ by Popeye 4.73)} Cyclic obstruction and cyclic anti-obstruction. (Author)

15 Responses to No.936 (GE)

1. shankar ram says:

Really fine use of disparate condition!

The B moves to g3 are more than obstruction. They incarcerate or prevent the 2 other pieces from _moving_ at all. In obstruction a piece is only prevented from moving to a _particular_ square. So we have a “cyclic incarceration” on g3.
The W pieces execute the anti-form of obstruction: square vacation. Here, if the disparate condition did not apply to W, we would have dual continuations. But since it does, W cannot make a move with the piece similar to the last B move.
Thus,
1…Sg3 Not 2.Sd2? for 3.Bb3#
1…Bg3 Not 2.Bd3? for 3.Rc4#
1…Rg3 Not 2.Rc6? for 3.Sc5#

So, in total, “B cyclic incarceration plus W cyclic square vacation with dual avoidance”!
The scheme is obviously “plug-hungry”, but other than the Ps, every W piece is utilised in at least one variation. And B has only the 3 thematic pieces.
Overall, great theme combination with excellent construction and economy. Well done, Georgy!

2. seetharaman says:

The cyclic square vacation is an old theme for white in orthodox #3. Here Georgy Evseev gives a new twist of combining it with incarceration of black pieces! Very nice!

3. Hubert Gockel says:

The pawn-key uses a neat “side effect” of the condition insofar all black pawns are condemned to linger on their diagram squares thus allowing a zugzwang situation in a crowded setting!

4. eugenerosner says:

really pretty idea! but is the position not illegal? B pawns need to capture thrice with only two men available…

• eugenerosner says:

make that 4 times!

5. dupont says:

With a Queen as last black thematic piece!

6. Luce Sebastien says:

Dear Georgy,
1) It is C+ Disparate (W&B) so I think it is more logical to use this condition which is the original one, wanted by Romeo Bedoni. Disparate Py is only a version created after and only usefull in some very special cases.
2) I have a version minus one piece :
White : Kç7 Qa6 Rb6ç5 Bç4ç1 Sb3a1 Pd6a5b5d5ç3d3
Black : Ka4 Rf3 Bh4 Sh1 Pg5f4é3h3f2
‡3 (14+9) C+
White Disparate
Black Disparate
1.d4! blocus
1…Sg3 2.Bf1 [3.Rç4‡]
1…Bg3 2.Rçç6 [3.Sç5‡]
1…Rg3 2.Sd2 [3.Bb3‡]
(I precise it is C+ with Disparate or Disparate Py)
3) Your idea is very pretty.
Sebastien Luce

7. Luce Sebastien says:

White Queen can also be on a8 to have a little more play
so I resend the position :
White : Kç7 Qa8 Rb6ç5 Bç4ç1 Sb3a1 Pd6a5b5d5ç3d3
Black : Ka4 Rf3 Bh4 Sh1 Pg5f4é3h3f2
‡3 (14+9) C+
White Disparate
Black Disparate
1.d4! blocus
1…Sg3 2.Bf1 [3.Rç4‡]
1…Bg3 2.Rçç6 [3.Sç5‡]
1…Rg3 2.Sd2 [3.Bb3‡]

8. Luce Sebastien says:

In fact, it is simpler to erase White Pawn e2 in your problem
and to put white Queen in a8 (I think it is better) so it is the following :
White : Kç7 Qa8 Rb6ç5 Bç4ç1 Sb3a1 Pa5b5d5ç3d3
Black : Ka4 Rf3 Bh4 Sh1 Pé7g5f4é3h3f2
‡3 (13+10) C+
White Disparate
Black Disparate
1.d4! blocus
1…Sg3 2.Bf1 [3.Rç4‡]
1…Bg3 2.Rçç6 [3.Sç5‡]
1…Rg3 2.Sd2 [3.Bb3‡]

9. shankar ram says:

How about a version with the 3 W 2nd moves as thematic tries, defeated by the 3 B moves to g3? You would get a nice Cyclic Banny too! Here, only the WR and WS can make tries.

10. Georgy Evseev says:

Well, I have not expected so active reaction to this problem. Many thanks for your opinions.

Frankly speaking, I myself am not happy with the construction of this problem, but this version is the best I was able to come with. I have an inner feeling that a much better rendering of idea is possible, but was not able to find cleaner position.

Concerning the different realization of Disparate condition in WinChloe and Popeye, I would be very much obliged if somebody will find time to explain the difference. For me the first statement of definition above the problem is very simple and does not seem to give a lot of freedom of interpretation.

Concerning changes proposed by Sebastien, I expect that removal of Pe2 leads to duals. It is interesting that WinChloe (with Disparate PY W&B condition) shows only 2.Bf1 after 1…Sg3, but if we check a twomover after 1.d4 Sg3, it considers all moves – 2.Bf1, 2.Be2, 2.Bd3 as correct. I do not understand the reason.

• shankar ram says:

>> I do not understand the reason.
Try disabling the hash table!

What about my suggestion to have 3 thematic tries?

11. Luce Sebastien says:

Dear Gyorgy,
In 3 moves if 1…Sg3 has been played, it paralyses the Knight & prohibits moves as 2.Sd2.
But 2.Be2 or f1 are also prohibited as 2…Sxe2! or 2…Sxf1! 3.Rc4 is not mate ! Because 3…Tg3 !! paralysing the Rc4.
It is not the case in 2 moves after 1.d4 Sg3 because the program didn’t know the “past” of the position !
I think you can erase Pawn e2 safely.
For the white Queen, you can see.
Best
Sebastien Luce

12. Luce Sebastien says:

Sorry Georgy,
After 1.d4 Sg3 2.Bf1 has to be played (instead of Be2 or Bd3) probably to avoid the promotion in Rook

13. Luce Sebastien says:

Ultimate comment :
C.Poisson just told me that there is a dual without e2 pawn.
(a problem with the new version of Winchloe)
So 1000 sorry Georgy
Sebastien Luce