[Retros] Retros Digest, Vol 146, Issue 2

[Nicolas Dupont]

>> Is it possible to construct a purely orthogonal mate without any   
>> capture, ie some NC#(a,0,0)?

> There's no example in 6.0 moves or less in my files.

Thanks François. The shortest I'm able to produce yet is NC#(38,0,0) in 9.0:

1. Pa2-a4   Ph7-h5     2. Pa4-a5   Th8-h6     3. Pa5-a6   Th6-f6
4. Ta1-a5   Tf6-f5     5. Ta5-e5   Pd7-d5     6. Ph2-h4   Dd8-d6
7. Th1-h3   Dd6-g6     8. Th3-e3   Pf7-f6     9. Pf2-f3   Dg6-g3#

Maybe there are not too many capture-free mate PG (sound!), so that  
you might compute all of them till such a bound?