[Retros] (no subject)

[Andrew Buchanan]

Folks,

Here is a 6-pawn-column position which I believe (and Euclide 0.91 tells 
me!) is dual-free. 

4k2r/3RPp1p/3QP3/4P3/4P3/2B1P3/1P2P1P1/1N2KB2
SPG in 18.5 

It might well be possible to create a still faster example. Alternatively, 
an extended challenge would be to have a (promoted) pawn on the 8th rank 
extending the column. It would be nice if that promoted unit were uniquely 
determined to avoid dual or obtrusion. 

Solution output by Euclide follows in a few lines. 

Cheers,
Andrew. 

**************************************************************************** 

Solution follows after 

Solution #1 :
 ---------------------------------------------------------------------
1. Ph2-h4   Pg7-g5     2. Ph4xg5   Cg8-f6     3. Th1-h6   Ff8xh6
4. Pg5xf6   Fh6-e3     5. Pf2-f4   Fe3xg1     6. Pf6xe7   Fg1-e3
7. Pd2xe3   Pb7-b5     8. Fc1-d2   Pb5-b4     9. Fd2-c3   Pb4-b3
10. Pa2xb3   Pc7-c5    11. Ta1xa7   Pc5-c4    12. Pb3xc4   Pd7-d5
13. Pc4xd5   Fc8-e6    14. Pd5xe6   Dd8-d3    15. Ta7-d7   Ta8-a4
16. Pc2xd3   Ta4-e4    17. Pd3xe4   Cb8-c6    18. Dd1-d6   Cc6-e5
19. Pf4xe5 

(end)