[Retros] EQUAL LAST MOVE - revised presentation

[raosorio at fibertel.com.ar]

Dear friends,

I'm correcting here some mistakes coming from P/B english/german notation and
touching a bit the definition  to make it more clear.
I keep the complete presentation in  order to make the things easy. 
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I'm presenting here a new stipulation (close to "last move") that I developed as a byproduct
during the current and excelent "Last Move type D" process that Mario Richter is managing in
this forum.

EQUAL LAST MOVE (ELM)- Definition 
Twinning a) white to move, b) black to move. Find the a) and b) "same  nature" legal last move.

The move's nature is determined by the type of the piece/pieces involved  (K, Q, R, B, N, P) and 
the type of movement (simple, straight promotion, simple capture, capturing promotion, e.p., 
pawn double step, O-O, O-O-O).

An ELM problem is not (in general) a Last Move type D one. The diagram could present many legal
candidates to be the last move, but there is just one for a) and just one for b) that are of
the same nature. On the contrary, all the Last Move type DD problems are particular ELM ones.

There are 60 theorical cases. We are trying here to find the economy records (minimal pieces
number). On top of records, I think that this stipulation could be used to composse some nice
problems with many tries.

After my first 20.04.2007 example I received this week many others. Thanks to Werner Keym and 
Bernd Schwarzkopf for their valuable help. I present here the first updating remarking that
there are more than 30 cases still pending, so please collaborate to fill the gaps and improve
the existing records.

Some examples are a light variation of the previous Type B ones and they are indicated as such.

You can send your originals via this RML or via private mail to me.

Best regards,
Roberto Osorio


K-    (3+2=5)   (8/8/8/6R1/7k/8/7K/6Rb)  Bernd Schwarzkopf/9.05.2007
KxQ   (2+11=13) (8/ppppppp1/7p/7R/7K/8/7k/6nn) Bernd Schwarzkopf/9.05.2007
KxR   (3+3=6)   (bK6/8/bk6/NP6/8/8/8/8)  Bernd Schwarzkopf/9.05.2007
KxB   (2+3=5)   (K1k5/2rp4/2P5/8/8/8/8/8 ) Bernd Schwarzkopf, Werner Keym/9.05.2007 
KxN   (3+2=5)   (K7/8/k7/P7/8/8/7b/6Q1)  Bernd Schwarzkopf/9.05.2007
KxP   (1+5=6)   (8/8/8/1q1r4/k7/n1K5/5q2/8) Bernd Schwarzkopf/9.05.2007

Q-    (8+3=11)  (8/8/8/8/8/1P6/bPPPP1K1/Q1Bkq3) Bernd Schwarzkopf/9.05.2007

R-    (5+4=9)   (8/8/8/7p/4k2r/6KP/5PP1/6bR)  Bernd Schwarzkopf/9.05.2007

B-    (7+4=11)  (8/8/1p6/b7/8/P2P4/P1kPP3/K1Bb4) Bernd Schwarzkopf/9.05.2007
BxN   (4+5=9)   (2b5/3p4/8/8/8/6P1/5Pr1/3k1KBr) Bernd Schwarzkopf/9.05.2007

N-    (5+3=8)   (8/8/8/8/8/8/kPP1P3/Nbn1K3) Bernd Schwarzkopf/9.05.2007
NxQ   (3+10=13) (1nbk2NR/1p1ppppK/p6p/8/8/8/8/8) B.Schwarzkopf/9.05.2007 (Type B,V. Bartolovic, R. Buljan)

P-    (2+2=4)   (8/8/8/8/8/6P1/7p/5K1k)  Roberto Osorio/20.04.2007
P--   (3+3=6)   (8/7p/7P/6pK/5k1P/8/8/8) Bernd Schwarzkopf/9.05.2007
PxQ   (3+9=12)  (8/8/8/8/4N1K1/5P1P/6Pp/4BkNb) Bernd Schwarzkopf/9.05.2007
PxR   (7+2=9)   (8/8/8/4KR2/7P/7P/6Pp/5BkN) Bernd Schwarzkopf/9.05.2007
PxB   (6+2=8)   (8/8/8/4KN2/7P/7P/6Pp/6Nk) Bernd Schwarzkopf/9.05.2007
PxN   (5+2=7)   (8/6K1/7P/8/8/7P/6Pp/6Nk)  Bernd Schwarzkopf/9.05.2007
PxP   (5+2=7)   (8/4K3/8/8/7P/5N1N/6Pp/7k) Bernd Schwarzkopf, Werner Keym/9.05.2007

P-=Q  (5+2=7)   (7Q/8/8/7P/8/6K1/6P1/5Bkq) Bernd Schwarzkopf/9.05.2007
P-=R  (5+2=7)   (7R/8/8/8/8/6P1/5K1P/5Brk) Bernd Schwarzkopf/9.05.2007
P-=B  (2+3=5)   (7B/6p1/8/8/8/7K/8/6bk)   Bernd Schwarzkopf/9.05.2007
P-=N  (2+4=6)   (7N/8/8/8/8/8/5pr1/3k1K1n) Bernd Schwarzkopf/9.05.2007 

PxQ=Q (2+12=14) (nQr1n3/1ppKp1p1/kp1pp3/8/8/8/8/7q) Werner Keym/9.05.2007
PxQ=R (2+12=14) (nRr1n3/1ppKp1p1/kp1pp3/8/8/8/8/7r) Werner Keym/9.05.2007
PxR=R (7+2=9)   (7R/5K2/6P1/8/8/1P6/kP6/NrB5) Bernd Schwarzkopf/9.05.2007
PxB=R (5+2=7)   (R7/2K5/1R6/8/8/P7/k7/rR6) Bernd Schwarzkopf/9.05.2007
PxN=R (4+2=6)   (1R6/2K5/8/8/8/P7/k7/rR6) Bernd Schwarzkopf/9.05.2007
PxN=Q (2+6=8)   (KQn5/1pp5/kp6/8/8/8/8/q7) B.Schwarzkopf/9.05.2007 (Type B,many authors)