[Retros] Capture at home + mate at home

[Nicolas.Dupont at math.univ-lille1.fr]

>> So it's done with bishop or queen.  I think that is it impossible

>> in the rook case, but possible in the knight case, although I'm

>> unable to construct it for the moment...

>

> The "rook case" looks difficult but I am not convinced that it is

> impossible.  Have you tried starting with something like

>

>   1 h4 b5 2 Rh3 Bb7 3 Ra3 Be4 4 Ra6 c6 5 a4 Qa5 6 Rb6 Na6 7 Ra3 Kd8

>   8 Rb8+ Kc7 9 Rxa8


Yes I do. And also with 1.h4 g5 2.h5 g4 3.Rh4 g3 4.Rg4 Nh6 5.Rg8 f6
6.Rxh8 Kf7 7.Rg8 Ke6 8.Rg4 Kd4e4f4 9.Rh4 Ng4 giving free black moves via Bh6.

But the problem is that this "rook case" involves at least 8 moves to
capture its opponent and go back home. Moreover, check-mate by Rh1 (or
Ra1) leads to a previous move by Ng1 (or Nb1), and  this knight seems
therefore to have enough time to capture the black rook, instead of the
white rook.

Nevertheless, I haven't a clear proof that this "rook case" is really
impossible. But I will be very surprised if someone can realyse it.