# [Retros] Infinite length HAP problem

Francois Labelle flab at EECS.Berkeley.EDU
Sat Dec 1 17:53:48 EST 2007

On Sat, 1 Dec 2007, Joost de Heer wrote:

> This is a draw after a few moves :)

Well the infinite game I had in mind is

1. Nc3 Nc6 2. Nd5 Nd4 3. Nxe7 Nxe2 4. Nxg8 Nxg1 5. Nh6 Nh3 6. Nxf7 Nxf2 7.
Nxh8 Nxh1 8. Nf7 Nf2 9. Kxf2 Kxf7 10. Rb1 Rb8 11. Ra1 Ra8 ...

which is legal according to the FIDE Laws of Chess. So I see three
possibilities:

1) HAP forces players to claim a draw when it is possible. This leads to
the ugly property that not all legal chess games can be written in HAP
notation. My problem doesn't work.

2) "=" means "a draw was automatic or was possible", in which case my
problem would be written:

[...] 14.A A 15.A A= 16.A= A= ...

3) "=" means "a draw was automatic or was claimed", in which case my
problem would be written:

[...] 14.A A 15.A A 16.A A ...

Francois

P.S.: Your proposal for a3 is cooked:
1. a3 e5 2. Nf3 Bxa3 3. Nxe5 Bxb2 4. Rxa7 Rxa7
1. a3 e5 2. Nf3 Bxa3 3. Nxe5 Bxb2 4. Nxd7 Nxd7
1. g4 d5 2. Nc3 Bxg4 3. Nxd5 Bxe2 4. Nxe7 Nxe7
1. h3 d5 2. Nc3 Bxh3 3. Nxd5 Bxg2 4. Rxh7 Rxh7
1. h3 d5 2. Nc3 Bxh3 3. Nxd5 Bxg2 4. Nxe7 Nxe7