MESON Chess Problem Database
Problem Display
PID: 153495 (8/8/8/5Rp1/4p1K1/4P3/Rb3PNB/3BNk2 w - - 0 1)
Harley, Brian
The Observer, 1942
(First published on Sun Oct 11 1942)
#2
9 + 4
| 15290 | Harley Scrapbook | 2014 |
| 15239 | Valois Notebooks | 2019 |
SOLUTION
- SOUND
- Sets
- 1...Ba1
- 2.Be2#
- 1...Bc1
- 2.Be2#
- 1...Ba3
- 2.Be2#
- 1...Bc3
- 2.Be2#
- 1...Bd4
- 2.Be2#
- 1...Be5
- 2.Be2#
- 1...Bf6
- 2.Be2#
- 1...Bg7
- 2.Be2#
- 1...Bh8
- 2.Be2#
- 1...Ba1
- Tries
- 1.Kh3?
- 1...Ba1
- 2.Be2#
- 1...Bc1
- 2.Be2#
- 1...Ba3
- 2.Be2#
- 1...Bc3
- 2.Be2#
- 1...Bd4
- 2.Be2#
- 1...Be5
- 2.Be2#
- 1...Bf6
- 2.Be2#
- 1...Bg7
- 2.Be2#
- 1...Bh8
- 2.Be2#
- 1...g4+!
- 1...Ba1
- 1.Kxg5?
- 1...Ba1
- 2.Be2#
- 1...Bc1
- 2.Be2#
- 1...Ba3
- 2.Be2#
- 1...Bc3
- 2.Be2#
- 1...Bd4
- 2.Be2#
- 1...Be5
- 2.Be2#
- 1...Bg7
- 2.Be2#
- 1...Bh8
- 2.Be2#
- 1...Bf6+!
- 1...Ba1
- 1.Kh5?
- 1...Ba1
- 2.Be2#
- 1...Bc1
- 2.Be2#
- 1...Ba3
- 2.Be2#
- 1...Bc3
- 2.Be2#
- 1...Bd4
- 2.Be2#
- 1...Be5
- 2.Be2#
- 1...Bf6
- 2.Be2#
- 1...Bg7
- 2.Be2#
- 1...Bh8
- 2.Be2#
- 1...g4!
- 1...Ba1
- 1.Bf3?
- 1...Kxf2
- 2.Bd1#
- 1...Ba1
- 2.Be2#
- 1...Bc1
- 2.Be2#
- 1...Ba3
- 2.Be2#
- 1...Bc3
- 2.Be2#
- 1...Bd4
- 2.Be2#
- 1...Be5
- 2.Be2#
- 1...Bf6
- 2.Be2#
- 1...Bg7
- 2.Be2#
- 1...Bh8
- 2.Be2#
- 1...exf3!
- 1...Kxf2
- 1.Rf3?
- 1...Ba1
- 2.Be2#
- 1...Bc1
- 2.Be2#
- 1...Ba3
- 2.Be2#
- 1...Bc3
- 2.Be2#
- 1...Bd4
- 2.Be2#
- 1...Be5
- 2.Be2#
- 1...Bf6
- 2.Be2#
- 1...Bg7
- 2.Be2#
- 1...Bh8
- 2.Be2#
- 1...exf3!
- 1...Ba1
- 1.Rf4?
- 1...Ba1
- 2.Be2#
- 1...Bc1
- 2.Be2#
- 1...Ba3
- 2.Be2#
- 1...Bc3
- 2.Be2#
- 1...Bd4
- 2.Be2#
- 1...Be5
- 2.Be2#
- 1...Bf6
- 2.Be2#
- 1...Bg7
- 2.Be2#
- 1...Bh8
- 2.Be2#
- 1...gxf4!
- 1...Ba1
- 1.Rf6?
- 1...Ba1
- 2.Be2#
- 1...Bc1
- 2.Be2#
- 1...Ba3
- 2.Be2#
- 1...Bc3
- 2.Be2#
- 1...Bd4
- 2.Be2#
- 1...Be5
- 2.Be2#
- 1...Bxf6!
- 1...Ba1
- 1.Rf7?
- 1...Ba1
- 2.Be2#
- 1...Bc1
- 2.Be2#
- 1...Ba3
- 2.Be2#
- 1...Bc3
- 2.Be2#
- 1...Bd4
- 2.Be2#
- 1...Be5
- 2.Be2#
- 1...Bg7
- 2.Be2#
- 1...Bh8
- 2.Be2#
- 1...Bf6!
- 1...Ba1
- 1.Rf8?
- 1...Ba1
- 2.Be2#
- 1...Bc1
- 2.Be2#
- 1...Ba3
- 2.Be2#
- 1...Bc3
- 2.Be2#
- 1...Bd4
- 2.Be2#
- 1...Be5
- 2.Be2#
- 1...Bg7
- 2.Be2#
- 1...Bh8
- 2.Be2#
- 1...Bf6!
- 1...Ba1
- 1.f3?
- threat
- 2.fxe4#
- 1...Kf2
- 2.fxe4#
- 1...exf3
- 2.Rxf3#
- 1...Be5!
- threat
- 1.Kh3?
- Keys
- 1.f4!
- threat
- 2.fxg5#
- 1...Kf2
- 2.fxg5#
- 1...gxf4
- 2.Rxf4#
- 1...exf4 ep
- 2.Rxf3#
- 1...Be5
- 2.fxe5#
- threat
- 1.f4!
FEATURES
- Static
- TYPE = BLOCK_THREAT
- CHANGED MATES = 1
- ADDED MATES = 3
- REMOVED MATES = 8
- Sets
- B(b);::B(A)
- Tries
- Try
- K(H);S_FLIGHT
- Vars
- B(b);::B(A)
- Refutation
- P(d);CHECK
- Try
- K(H);P-FLIGHT,XP(d)
- Vars
- B(b);::B(A)
- B(b);P_PINP(G)::B(A)
- Refutation
- B(b);CHECK
- Try
- K(H);S_FLIGHT
- Vars
- B(b);::B(A)
- Refutation
- P(d);
- Try
- B(A);
- Vars
- K(a);OGATEB,P-FLIGHT,P_SPINB(b),XP(D)::R(I)+B(A)
- B(b);::B(A)
- Refutation
- P(c);XB(A)
- Try
- R(I);
- Vars
- B(b);::B(A)
- Refutation
- P(c);XR(I)
- Try
- R(I);
- Vars
- B(b);::B(A)
- Refutation
- P(d);XR(I)
- Try
- R(I);
- Vars
- B(b);::B(A)
- Refutation
- B(b);XR(I)
- Try
- R(I);
- Vars
- B(b);::B(A)
- Refutation
- B(b);
- Try
- R(I);
- Vars
- B(b);::B(A)
- Refutation
- B(b);
- Try
- P(D);
- Threat
- R(I)+P(D),XP(c)
- Vars
- K(a);P-FLIGHT,P_SPINB(b)::R(I)+P(D),XP(c)
- P(c);OGATE,P_SPINP(c),XP(D)::R(I),XP(c)
- Refutation
- B(b);
- Try
- Actual
- P(D);
- Threat
- R(I)+P(D),XP(d)
- Vars
- K(a);P-FLIGHT,P_SPINB(b)::R(I)+P(D),XP(d)
- P(d);OGATE,P_SPINP(d),XP(D)::R(I),XP(d)
- P(c);EP,OGATE,P_SPINP(c),XP(D)::R(I),XP(c)
- B(b);OGATE::R(I)+P(D),XB(b)
Developed and maintained by Brian Stephenson.
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