No.1659 (MC&SKB&VN)

(C- : partially computer tested, see the notes below)

Comments by the Authors:
• Black AUW with all promotions on the same square by only one gate opening by white (1.d4!).
• All 4 promotions occur utilizing the fairy condition (PWC) effect by the same white piece which moves from the promotion square to capture black pawns.
• Paradox: All white pieces are on their home base, but the promoted pieces have already come out of the white castle before the door was closed.

Note by the Authors:
The problem is only partially computer tested and full test could not be conducted as it would take several weeks of continuous testing.
Following tests have been conducted:
• Tested by using Jacobi in Heuristic Mode. Did not give any cook.
• Tested by using Jacobi in Demolition Mode for 2 days. Gave only the intended solution.
• Tested by using Jacobi from Position ‘a’ to Position ‘b’ (a=>b), for the following values of a & b: a=1 b=9 / a=2 b=10 / a=3 b=11.
No cook was found for the above tests.