Birthday problem solutions

Birthday problems by Werner Keym

Here are the problems Werner Keym composed for Helmut Pfleger's eightieth birthday. In the first all the pieces are on the h-file (for "Helmut"), and stand on the ranks that give the date of his birth: 6.8.43.

In helpmates it is Black to move, and he must help White to mate him in the required number of moves. The solution here is: 1.Ng5 Kg6+ 2.Nh7 Kf5 3.Kh5 Rxh7#. There was a twin to the above problem: change the black knight on h3 into a white knight! 

Now the solution is 1.Kg4 Nf2+ 2.Kg3 Rg8+ 3.Kh4 Rg4#. Very nice, very clever. You know that we can follow the solution by moving the pieces on the board. 

In help-stalemates it is likewise required that Black (to move) helps White to stalemate him in the required number of moves. "Help-Stalemate" in German is "Hilfs-Patt" (H for Helmut and P for Pfleger), and the pieces stand on the rank that give the date of his birth: 6.8.43. The solution: 1.Kd4 Kb5 3.Kd5 Nf5 (knight stalemates).

Here Werner Keym had two twins to his puzzle – a single piece moved in each case, to yield a radically different solution:

Solution: 1.Ke4 Qg1 2.Kf4 Kd5 (king stalemates).

Solution: 1.Kd2 Qg6 2.Ke1 Qc2 (queen stalemates).

Each of the above solutions is unique – no alternatives lines are possible.