# [Retros] eight officers homebase mate - OPENED DEFINITION

raosorio at fibertel.com.ar raosorio at fibertel.com.ar
Fri Nov 24 13:59:12 EST 2006

Hi,

Pascal Wassong wrote,
"
Hello, I think that a case is missing: Q(sD)/0. It seems
to me possible to mate the bK on c2, with wPc2 and e2
missing"

and after that,

"And to answer my one question, here is what I found for case Q(sD)/0:

rsbq1bsr/1pp1pp1p/2p5/8/p7/8/PPkP1PPP/RSBQKBSR
9.5 moves. 14 + 15 "

Well done Pascal !. I didn't take into consideration this very special (the only
one n=0) and nice subcase. I'm including it here and reproducing the
complete presentation to make easy the follow up.

Rroberto Osorio

------------------------------------------------------------------------------------------------------
I present here the task version opened to different king position as
suggested by Andrew Buchanan.

I found that it's much reacher and challenging now. There are 32 different
records to find, both for material and dynamic approach, and some of them
will be not so easy.

I include the complete definitions and the Record Table, wich is now plenty
of room waiting for new achievments.

Roberto Osorio

EIGHT OFFICERS HOMEBASE MATE - CONCEPTUAL DEFINITION

CONSTRAINTS
PG diagram showing a mate position where the mating side has its 8 officers
at homesquare and the remaining pawns at homesquare too. Standard material

CASES
There are 11 different cases based on the checking piece and the checking line.
Each case has n subcases, represented as /n. The extension /n means the nbr of empty
squares separating the mating piece and the mated king. Of course, there
are no subcases for the knight cases.

R(h)/n - mate by rook on (h) row, n from 2 to 6
R(a)/n - mate by rook on (a) row, n from 2 to 6
B(c)/n - mate by c1/c8 bishop, n from 1 to 4
B(f)/n - mate by f1/f8 bishop, n from 1 to 4
Q(lD)/n - mate by queen on its homesquare long diagonal, n from 2 to 3
Q(sD)/n - mate by queen on its homesquare short diagonal, n from 0 to 2
Q(d)/n - mate by queen on (d) row, n from 2 to 6
N(b)K(a)- mate by knight from its b1/b8 homesquare and oposite king on a3/a6
N(b)K(c)- mate by knight from its b1/b8 homesquare and oposite king on c3/c6
N(g)K(f)- mate by knight from its g1/g8 homesquare and oposite king on f3/f6
N(g)K(h)- mate by knight from its g1/g8 homesquare and oposite king on h3/h6

For instance, in the Q(sD) case n=1 defines the king position b3(black king) or
b6(white king). n=2 defines the king position a4(black king) or a5(white king).

This way, there are now 32 different cases/subcases, each one having it's own
potential record.

The subcase n ranges have been defined as the feseable ones from the geometrical
point of view without any further consideration.

Defining,

p: homebase mating side missing pawns
m: PG single moves
c: other side missing pieces

a PG is characterized as (p,m,c). The task asks for economy, so p, m and c have
to be minimized. Two different orders define two different tasks,

1) Material task: minimize first p, then m and finally c.
2) Dynamic task : minimize m, then p and finally c.

PRESENT RECORD STATUS (nov 24th 2006)
On the vacancy of a dynamic record the material one is considered to be
the double record.

************************************************************************
CASE/n......(p,m,c)...Author....................(p,m,c)....Author
************************************************************************
R(h)/2....- (1,20,2)..Nicolas Dupont
------------------------------------------------------------------------
R(h)/3....-
------------------------------------------------------------------------
R(h)/4
------------------------------------------------------------------------
R(h)/5....-.(1,16,2)..Andrew Buchanan
------------------------------------------------------------------------
R(h)/6....-.(1,14,2)..Andrew Buchanan
************************************************************************
R(a)/2....-.(1,26,3)..Nicolas Dupont
------------------------------------------------------------------------
R(a)/3
------------------------------------------------------------------------
R(a)/4
------------------------------------------------------------------------
R(a)/5
------------------------------------------------------------------------
R(a)/6,,,,-.(1,18,2)..Andrew Buchanan
************************************************************************
B(c)/1
------------------------------------------------------------------------
B(c)/2
------------------------------------------------------------------------
B(c)/3
------------------------------------------------------------------------
B(c)/4....-.(1,28,6)..R.Osorio & J.Lois.........(2,24,1).R.Osorio & J.Lois
************************************************************************
B(f)/1
------------------------------------------------------------------------
B(f)/2....-.(3,20,0).J.Lois & R.Osorio.........
------------------------------------------------------------------------
B(f)/3
------------------------------------------------------------------------
B(f)/4....-.(1,27,3)..J.Lois & R.Osorio
************************************************************************
Q(lD)/2
------------------------------------------------------------------------
Q(lD)/3...-.(1,27,4)..J.Lois & R.Osorio.........(2,18,4).Nicolas Dupont
************************************************************************
Q(sD)/0--- (1,19,2) Pascal Wassong
------------------------------------------------------------------------
Q(sD)/1
------------------------------------------------------------------------
Q(sD)/2...-.(2,20,2)..R.Osorio & J.Lois
************************************************************************
Q(d)/2
------------------------------------------------------------------------
Q(d)/3
------------------------------------------------------------------------
Q(d)/4
------------------------------------------------------------------------
Q(d)/5....-.(1,19,3)..J.Lois & R.Osorio.........(2,17,2).R.Osorio & J.Lois
------------------------------------------------------------------------
Q(d)/6
************************************************************************
N(b)K(a)-.(1,24,4)..R.Osorio & J.Lois
************************************************************************
N(b)K(c)-.(2,25,3)..
************************************************************************
N(g)K(f)-.(3,27,5)..R.Osorio & J.Lois
************************************************************************
N(g)K(h)-.(1,24,4)..J.Lois & R.Osorio
************************************************************************

The proof games
------------------------------------------------------------------------
R(h)/5 (1,16,2) Andrew Buchanan
rnbqkbnr/ppppppp1/8/8/4P3/6P1/PPPPN1PK/RNB2BR1

R(h)/6 (1,14,2) Andrew Buchanan
rnbqkbnr/ppppppp1/8/8/4P3/3B4/PPPPNPP1/RNB3RK

R(a)/6 (1,18,2) Andrew Buchanan
rnbqkbnr/1ppppppp/8/8/3P1Q2/4B3/1PP1PPPP/KR3BNR

Q(d)/5 (1,19,3) Jorge Lois & Roberto Osorio
rnb1q3/pppkrp2/2p1p2p/8/8/8/PPP1PPPP/RNBQKBNR

Q(d)/5 (2,17,2) Roberto Osorio & Jorge Lois
rnb1qbn1/p1pkppp1/2p1p3/8/8/8/PP2PPPP/RNBQKBNR

Q(lD)/3 (1,27,4) Jorge Lois & Roberto Osorio
1n4n1/2q1p3/2pr2pr/6bk/7p/8/PPPP1PPP/RNBQKBNR

Q(lD)/3 (2,18,4) Nicolas Dupont
rnbqkbnr/ppp2ppp/8/4P2B/7K/6B1/PP4PP/RN4NR

Q(sD)/0 (1,19,2) Pascal Wassong
rsbq1bsr/1pp1pp1p/2p5/8/p7/8/PPkP1PPP/RSBQKBSR

Q(sD)/2 (2,20,2) Roberto Osorio & Jorge Lois
rsbqkbsr/pp1p1ppp/8/KB6/P7/4PS2/1PP2PPP/1SBQ3R

B(f)/4 (1,27,3) Roberto Osorio & Jorge Lois
1n4n1/rpp3p1/kb3r2/p3p1q1/8/7b/PPPP1PPP/RNBQKBNR

B(f)/2 (3,20,0) Jorge Lois & Roberto Osorio
rsbqkbsr/p1p2ppp/8/1PK5/2R5/3P1Q2/1PPP1PPP/1SB2BSR

B(c)/4 (1,28,6) Jorge Lois & Roberto Osorio
rnbqkbnr/ppp1pppp/8/2P5/7P/6BK/P3P1PQ/5NN1

B(c)/4 (2,24,1) Roberto Osorio & Jorge Lois
rsbqkbsr/ppp2ppp/2P5/8/8/3PP1BK/P2PS1PP/RS1Q1B1R

N(g)K(h) (1,24,4) Jorge Lois & Roberto Osorio
rnbqkbnr/ppppppRp/7K/6BP/8/4P3/PP3PP1/1N1Q2N1

N(g)K(f) (3,27,5) Roberto Osorio & Jorge Lois
3q1bs1/5p1p/5p2/3p4/4r1b1/5k2/PPP1sP1P/RSBQKBSR

N(b)K(a) (1,24,4) Roberto Osorio & Jorge Lois
rnbqkbnr/pRpppppp/K7/PB6/8/3P4/1PP3PP/1N1Q2N1

N(b)K(c) (2,25,3) Jorge Lois & Roberto Osorio
rn1q4/pppprpp1/8/8/1bn5/2k5/P1P1PPPP/RNBQKBNR
-------------------------------------------------------------------------