[Retros] Equal Last Move (ELM) - updating

[raosorio at fibertel.com.ar]

Dear friends,

I'm sending here the updated list of ELM records. The changes compared to the last list
(ending 2007) are marked here with "n)". I keep the complete presentation including the
definition in order to make the things easy for newcomers.

I've also included a fairy (LORTAP) one showing the e.p. case, wich is is not feasible with
orthodox chess, neither ELM nor LMD.  Both O-O and O-O-O cases are pending to be shown 
using some fairy stipulation.  Madrasi seems to be a proper one; "Double Maximmumer"
makes it (apparently) very easy both for ELM and even LMD but  the problem to be solved
is to bulid a legal position under this stipulation.

Best,
Roberto

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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 (surely 57 in practice due to castlings and e.p. ??) 
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. 

Some examples are a light variation of the previous Type B ones and they are indicated as such. 
Dates are reception ones, i) means improved from previous updating, and n) means new. 

I included the reference of the Last Move Type DD record (Type DD is the particular Type D cases 
where the last move is of the same nature both for WTM and BTM) in the form of DDxx, where xx 
is the number of pieces in the corresponding DD record. 

For instance, in the following first case the move is K-, after that DD12 indicates that the DD 
record uses 12 pieces, and after that (3+2=5) means that the ElM record uses 3 white pieces 
and 2 black pieces, total 5. Then, the FEN, author and reception date. 

K- DD12 (3+2=5) (8/8/8/6R1/7k/8/7K/6Rb) Bernd Schwarzkopf/9.05.2007 
KxQ DD24 (1+11=12)(3nK2k/ppppp2p/4p2n/7p/8/8/8/8) Bernd Schwarzkopf/14.06.2007 
KxR DD22 (3+3=6) (bK6/8/bk6/NP6/8/8/8/8) Bernd Schwarzkopf/9.05.2007 
KxB DD14 (2+3=5) (K1k5/2rp4/2P5/8/8/8/8/8 ) Bernd Schwarzkopf, Werner Keym/9.05.2007 
KxN DD10 (3+2=5) (K7/8/k7/P7/8/8/7b/6Q1) Bernd Schwarzkopf/9.05.2007 
KxP DD24 (1+5=6) (8/8/8/1q1r4/k7/n1K5/5q2/8) Bernd Schwarzkopf/9.05.2007 

Q- DD13 (5+4=9) (8/8/8/8/1p6/Pp6/qPP1k3/1QK5) Bernd Schwarzkopf 11.6.2007 
QxQ DD?? (9+3=12) (8/8/8/8/8/4P1PP/1K1kPBPq/3N1Q1b) Bernd Schwarzkopf 22.06.2007 
QxR DD?? (7+2=9) (8/8/8/8/1N6/kPP5/q1PP4/1QK5) Bernd Schwarzkopf/21.06.2007 
QxB DD?? (7+3=10) (8/8/8/8/8/PK2B3/1pN1R3/QRqk4) Bernd Schwarzkopf 21.06.2007 
QxN DD12 (5+2=7) (8/8/8/8/8/P7/1PP5/qQK1k3) Thierry Le Gleuher /14.05.07 
 n) QxP DD26 (7+4=11) (5KNk/5p1q/5P1Q/5PPP/6p1/8/8/8) Bernd Schwarzkopf & Werner Keym/13888 Die Schwalbe, X 2008, page 599
 
R- DD13 (5+3=8) (8/8/8/8/1p6/P7/rPP1k3/1RK5) Bernd Schwarzkopf/08.06.2007 
RxQ DD17 (10+3=13) (8/8/8/8/8/P1P5/rP1PPPPP/kr1RK3) Bernd Schwarzkopf, Werner Keym/21.06.2007 
RxR DD?? (8+2=10) (8/8/8/8/BPK5/1R1P4/BNk5/r1B5) Bernd Schwarzkopf, Roberto Osorio, Jorge Lois/21.06.2007 
RXB DD18 (4+4=8) (8/8/8/8/1p6/p7/rPP1k3/1RK5) Bernd Schwarzkopf/08.06.2007 
RXN DD9 (3+4=7) (8/8/8/8/8/np6/rP2k3/1RK5) Bernd Schwarzkopf/08.06.2007 
RxP DD25 (6+2=8) (8/8/4K3/8/7P/4N1NR/5Pr1/6k1) Werner Keym/21.06.2007 

B- DD12 (7+4=11) (8/8/1p6/b7/8/P2P4/P1kPP3/K1Bb4) Bernd Schwarzkopf/9.05.2007 
BxQ DD24 (9+2=11) (8/8/6P1/4PPP1/7B/5P1P/5KPb/7k) Werner Keym/21.06.2007 
BxR DD11 (2+6=8) (5b1B/4pK1k/5ppp/8/8/8/8/8) Bernd Schwarzkopf/21.06.2007 
BxB DD27 (6+4=10) (4RBkb/3Pp2p/4KPP1/8/8/8/8/8) Bernd Schwarzkopf, Werner Keym/21.06.2007 
BxN DD11 (6+2=8) (8/8/8/8/8/4P1PP/5BPb/4K2k) Bernd Schwarzkopf/06.06.2007 
BxP DD26 (8+3=11) (8/8/6P1/6P1/3K1P1B/7N/5PPb/6nk) Werner Keym/21.06.2007 

N- DD11 (5+2=7) (8/8/8/8/8/5K2/4PPPk/6Nn) Bernd Schwarzkopf/08.06.2007 
NxQ DD17 (3+4=7) 6Nk/4p1Rn/4K2p/8/8/8/8/8 Bernd Schwarzkopf, Werner Keym/24.06.07 
 n) NxR DD16 (5+3=8) (6Nk/4pP1n/6KP/6P1/8/8/8/8) Bernd Schwarzkopf / 13456 (right side) Die Schwalbe, VIII 2007, page 201
 n) NXB DD19 (4+4=8) (8/8/8/8/1P6/pk6/Nr1P4/Kn6) Bernd Schwarzkopf / 13456 (left side) Die Schwalbe, VIII 2007, page 201 
NXN DD17 (5+3=8) (8/8/8/8/7P/4K1kP/6Pn/6Nb) Bernd Schwarzkopf/12.06.2007 
 n) NxP DD25 (7+3=10) (8/8/8/5P2/5KPn/7p/6PN/5BBk) Valentin Blacker/13524 Die Schwalbe, X 2007, page 257

P- DD8 (2+2=4) (8/8/8/8/8/6P1/7p/5K1k) Roberto Osorio/20.04.2007 
P-- DD17 ( 3+3=6) (8/7p/7P/6pK/5k1P/8/8/8) Bernd Schwarzkopf/9.05.2007 
PxQ DD24 (3+7=10) (8/8/8/8/4N1K1/5P1P/6Pp/4BkNb) Bernd Schwarzkopf/9.05.2007 
PxR DD21 (7+2=9) (8/8/8/4KR2/7P/7P/6Pp/5BkN) Bernd Schwarzkopf/9.05.2007 
PxB DD16 (6+2=8) (8/8/8/4KN2/7P/7P/6Pp/6Nk) Bernd Schwarzkopf/9.05.2007 
PxN DD16 (5+2=7) (8/6K1/7P/8/8/7P/6Pp/6Nk) Bernd Schwarzkopf/9.05.2007 
PxP DD18 (5+2=7) (8/4K3/8/8/7P/5N1N/6Pp/7k) Bernd Schwarzkopf, Werner Keym/9.05.2007 

P-=Q DD20 (5+2=7) (7Q/8/8/7P/8/6K1/6P1/5Bkq) Bernd Schwarzkopf/9.05.2007 
P-=R DD20 (5+2=7) (7R/8/8/8/8/6P1/5K1P/5Brk) Bernd Schwarzkopf/9.05.2007 
P-=B DD10 (2+3=5) (7B/6p1/8/8/8/7K/8/6bk) Bernd Schwarzkopf/9.05.2007 
P-=N DD16 (2+4=6) (7N/8/8/8/8/8/5pr1/3k1K1n) Bernd Schwarzkopf/9.05.2007 

 n)PxQ=Q DD24 (3+9=12) (nQr1B3/1ppKpp2/kp6/8/8/8/8/7q) Werner Keym / 13455 Die Schwalbe, VIII 2007, page 201 
 n) PxQ=R DD23 (4+6=10) (6R1/4pp2/5ppK/8/8/8/6R1/5Nrk) Bernd Schwarzkopf & Werner Keym 2009-03-11
PxQ=B DD25 (2+11=13) (2b1B3/pp1pp1p1/6p1/8/8/1k6/2rp4/bK6) Werner Keym/21.06.2007 
 n) PxQ=N DD24 (5+6=11) (6N1/4pp2/5ppK/8/8/6B1/6R1/5Bnk) Werner Keym & Bernd Schwarzkopf/new 2009-03-11
 
 n)PxR=Q DD?  (2+8=10) nQb5/Kp6/3p4/8/n7/1p6/2k5/q7 Werner Keym 18.6.2007 
PxR=R DD?? (7+2=9) (7R/5K2/6P1/8/8/1P6/kP6/NrB5) Bernd Schwarzkopf/9.05.2007
PxR=B DD24 (2+8=10) (4rnBr/5Kp1/4r3/8/8/1p6/2k5/b7) Jorge Lois & Roberto Osorio/2.06.07 
PxR=N DD24 (3+6=9) (5bNN/6pK/6p1/8/8/6p1/5k2/7n) Bernd Schwarzkopf/22.06.2007 

PxB=Q DD26 (2+6=8) (5nQK/5pr1/8/8/8/1p6/2k5/q7) Jorge Lois & Roberto Osorio/14.06.07 
PxB=R DD16 (5+2=7) (R7/2K5/1R6/8/8/P7/k7/rR6) Bernd Schwarzkopf/9.05.2007 
PxB=B DD25 (2+6=8) (5nBK/5pr1/8/8/8/1p6/2k5/b7)Jorge Lois,Roberto Osorio & Werner Keym/23.06.07 
 n) PXB=N DD16 (4+3=7) (5+2=7) (7N/5K2/6R1/8/8/7P/7k/6Rn) Bernd Schwarzkopf/new 2009-03-10 

PxN=Q DD23 (5+2=7) (5nQK/5pr1/8/8/8/8/2k5/1q6) Roberto Osorio & Jorge Lois/16.06.07 
PxN=R DD14 (4+2=6) (1R6/2K5/8/8/8/P7/k7/rR6) Bernd Schwarzkopf/9.05.2007 
 n) PxN=B DD24 (2+7=9) (2+5=7) (5nBK/5pr1/8/8/8/8/2k5/1b6) Bernd Schwarzkopf & Roberto Osorio & Jorge Lois/new 2009-03-10
PxN=N DD22 (2+5=7) (6KN/5r1r/6n1/8/8/8/2k5/1n6) Jorge Lois & Roberto Osorio/2.06.07 
 
 
 PxP e.p. (7+4=11) (5R1k/4n1PP/5Pp1/8/8/6Kp/B7/B7) LORTAP CHESS/ Roberto Osorio /Tournoi de composition ISC 2008
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