No.1488 (ND)

 No.1488 Nicolas Dupont (France) Original Retro & PG problems JF – R2019-20

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 No.1488 Nicolas Dupont France original – 21.03.2020 Solution: (click to show/hide) white Bf1c1 Ke1 Qd1 Ph2g2f2e2d2c2b2a2 Sg1b1 Rh1a1 black Bf8c8 Ke8 Qd8 Ph7g7f7e7d7c7b7a7 Sg8b8 Rh8a8 PG 13.5                                   (16+16) Leffie Back home 1.e2-e3 c7-c5 2.Bf1-b5 c5-c4 3.Sg1-e2 h7-h5 4.0-0 c4-c3 5.Bb5-d3 Rh8-h6 { } 6.Bd3-h7 Rh6-a6 7.f2-f3 Ra6-a4 8.Bh7-d3 Sb8-c6 9.Bd3-a6 Sc6-e5 10.Kg1-f2 Se5-g6 { } 11.Rf1-h1 Sg6-h8 12.Se2-g1 g7-g6 13.Ba6-f1 b7-b5 14.Kf2-e1 {dia (C+ Jacobi (Author))} Come and go castling in a capture-free proof game (maybe a novelty)! The motivation for the castling is a tempo manoeuver – the dynamic of the game implies that Bh7 must be played as soon as possible (Se5 cannot be played earlier as Bd3 is then illegal and the white side is squeezed), and 3.Se2 4.O-O is the only waiting sequence to achieve this goal. The problem is thematic for the Quartz TT13 but I found it after the deadline - it is C+ Jacobi. (Author)

4 Responses to No.1488 (ND)

1. Geoff Foster says:

A fantastic problem! The path of the wBf1 is especially good. There are plenty of Leffie effects, as follows:
2.Ba6?? is illegal because bSb8 would observe wBa6.
The Back-home move 4.Sg1?? is illegal because wQd1 would observe bPh5.
9.Bb5?? is illegal because wBb5 would observe bRa4.

2. Nikola Predrag says:

Moves like 2.Ba6?? are simply illegal. It’s not even trivial, it’s just the rules. It seems nonsensical to ask ‘why to choose a legal move instead of an illegal move’.
The point is in choosing AMONG THE LEGAL moves – ‘why this and not that LEGAL move’. A ‘Leffie effect’ makes sense when the illegality is the result of certain MOVE/PLAY, when the particular choice of moves creates such a ‘Leffie effect’.

The problem is fantastic because the intertwined conditions give birth to the new, transcendent features.

2.Bb5 c4 is a critical move & line-closure to prevent the ‘Back home’ 3.Bb5-f1
3.Se2 does the same (but anticipatory, to allow the line-opening 4…c3)
3…h5 pins wS, preventing ‘Back home’ Se2-g1
4.?? is the central point of the idea. White needs an ‘odd tempo’ to allow 4…c3 5.Bd3 (e.g. 4.Sa3? c3 5.Sb1). 4.f3? is ‘odd’ but unpins wS (4…c3 5.Sg1)
4.0-0 is the only good ‘odd’ choice at the moment but in the end it becomes ‘evened’ (4 moves altogether)
5…Rh6 6.Bh7 (critical&line-closure) enables 6…Ra6, which with 7…Ra4 determines (by departure) the timing of 8.Bd3 and the unique arrival 9.Ba6 (9.Bb5 is MADE illegal by the CHOSEN arrival of bR)
11.Rh1!(11.Ke1?/Sg1??) is the unique good choice among 3 ‘Back home’ moves (11.Ke1 leaves no time for ‘Back home’ by wB before 13…b5)

However, why that particular arrival 7…Ra4 is necessary, since 9.Ba6 is needed to prevent ‘Back home’ 9…Sb8 ?

3. dupont says:

Thanks friends for your elogious comments. Almost all thematic points have been listed. I played 6…Ra6 to get the opportunity to then play the important waiting move 7.f3 safely. Then 7…Ra5/a4/a3 are possible – I choosed square a4 just because a black rook should stand on a white colored square when possible (for a better visual effect).

4. Paul Raican says:

This is another little jewel by Nicolas. By the way, he made a collection of such pgs (with Leffie condition) with the occasion of TT13 Quartz, recently judged by V. Crișan. See http://quartz.chessproblems.ca/pdf/49/Quartz49.pdf