Christmas Contest, 2005

75 participants send their solutions, 51 of them made it to the drawing lot. Here are the winners:

1^{st} Prize (Philips-television): Horst Kiemele (Leonberg)

2^{nd} Prize (DVD player): Ralf Feest (Holzgerlingen)

3^{rd} Prize (Digital camera): Thomas Lutzius (Stuttgart)

A - **Günther Weeth**

Stuttgarter Zeitung, 12/2005 (Original)

"Last battle on b8"

Wrong is 1... Ba7xb8+. It may seem that black has no last move, but possible is Kc8-d8 and before that wPc7xTb8=N+. Or Kc8xd8 and before that wPc7xd8. So the correct solution is 1. Rc8++.

B - **Werner Keym and Günther Weeth**

Stuttgarter Zeitung, 12/2005 (Original)

"Eternal rest on a8?"

There are three solutions:

+Ke8, Rd8 and 1. Nc7++

+Kc6, Rb5 and 1. Nab8++

+Kc8, Rd8 and 1. Nb6++. Here black has only one possible last move: 0-0-0.

+Ka7, Ra7 and 1. Nb6 is not a solution, as here black has no last move.

Expert contest: Only 6 people did not fail. Among the 48 sender the following people master all puzzles and they were not misled by unforeseen traps:

Dietmar Fauth, Norbert Geisler (Munich), Andrej Frolkin (Kiew), Hannu Harkola, Olli Heimo, Hannu Lehto (Finland).

The follwing five people missed one partial solution:

Hans Bergmann (Aalen), Jens Guballa (Tamm), Mario Richter (Berlin), Klaus Wenda (Wienna), Markus Zehender (Ulm).

Also worth a book prize were the solutions of Norbert Derksen (Konstanz), Randolf Eilenberger (Dossenheim), Kurt Lorenz (Marbach), Rolf Sandau (Oberstenfeld), Ronald Schäfer (Aalen), Bernd Schwarzkopf (Neu?#376;), Nils Empacher, Thomas Lutzius and Rolf Schreiber (Stuttgart).

Here are the numbers of correct solver per problem:

C: 14

D: 11

E: 36

C - **Werner Keym**

Stuttgarter Zeitung, 12/2005 (Original)

Four solutions:

[8/8/8/8/1k6/P7/1K4P1/8]

Last move was a2-a3, so a white bishop never occured on a2, g2 and h1.

[8/8/8/8/1k6/P7/1KP5/8]

Here the squares are a2, b1 and c2

[8/6k1/7p/6K1/8/8/6P1/8]

Here g2, h1 and h7 were unreachable for the white bishop. The mirrored positions (e.g. wKb2, bKb4, wPa3, bPb7) are not correct solutions as a promoted white bishop may have occupied the square a8 or g8.

And the final solution "not really surprising for those who know the problems of Werner Keym" (Schwarzkopf):

[2kr2K1/3p4/8/8/8/8/8/8]

Last move was ... 0-0-0+, so the squares a8, d7 and e8 were never occupied by a white bishop.

D - **Günther Weeth**

Stuttgarter Zeitung, 12/2005 (Original)

White retracts three, black retracts two moves. Then white checkmates in two moves. Defensive Retractor, i.e. black does not cooperate during the retraction, so he has a choice.

Back 1. Le3xLc5? fails due to ...Ld4xLc5.

The planned solution is 1. Bg1xPc5! c6-c5+ 2. Kc5xPb4 b5-b4+ 3. Bh2xBg1! (before that: Pf2xXg1=B+).

In this position the castling 0-0 is prevented the retro analysis, so that 1. Kc5xc6 and 2. Rb7-b8 checkmates.

The position shows that on both sides the pawns have captured five times, otherwise the bPa3 could not have passed the white pawns. One white piece was captured by Pf2xXg1=B+, so all eleven missing pieces are "explained". The white h-pawn has promoted on h8 without a capture, so the bRh8 must have moved. The promoted pawn was captured then somewhere else.

Besides this also the following solution is possible (with some duals):

Back: 1. Bb5xNa6 Nb8-a6+ 2. L~xPc5 c6-c5+ 3. Bc5-~ or 1. Bd4xPc5 c6-c5+ 2. Bc5xQd4 Q~-d4+ 3. b5-b6 and in both cases 1. Rb7(x)b8+ Ke8-d7 2. b5xc6++.

This cook was first reported by M. Richter.

The idea is correctly presented in the following position:

[4k2r/R1p2p2/pP1P1P2/r1BP1p2/PKP2p2/8/6P1/1n1b4]

E - **Jens Guballa and Werner Keym**

Stuttgarter Zeitung, 12/2005 (Original)

+bPa3, 1. Qg5 and 2. Qd8++, because black may not castle anymore. The white king has no way back to e1 via the queen side, so he must have come via g6-f7-e7(e8)-d8.

First the wQ has to be retracted to d1, then the wK goes back via d8 to e1 and the wBg6 retracts to f1. Now the pawn g3 moves back to g2 and the wBg1 goes to c1. Finally wPb3->b2 and bBb1->c8. For the sceptict here the evolution of the final position starting from the initial position:

wPa2xNb3, wPh2-h4, bPe7xNd6xRc5xRb4, wNxPf7, bPb7xNc6, bPh7-h5, wPh4xBg5-g6xQh7xNg8 (promotion in any piece) ->a3, bPb4xa3, wPb3-b4, bBc8->b1, wPb2-b3, wBc1->g1, wPg2-g3, wBf1->g8, bRa8->b6, bKe8->d6, wKe1->d8,c8, bRb6->f7, wQd1->c5, bKd6->e8, wBg8->g6.