MESON Chess Problem Database
Problem Display
PID: 102057 (8/1p2p3/1K2pp2/2Q1Pk1P/3R4/3N2pN/5bn1/5R1b w - - 0 1)
Penrose, Lionel Sharples
The Observer, 1937
(First published on Sun Apr 4 1937)
#2
8 + 9
| 6490 | yacpdb | 2009 |
| 15239 | Valois Notebooks | 2019 |
SOLUTION
- SOUND
- Sets
- 1...Se1
- 2.Rf4#
- 1...Se3
- 2.Rf4#
- 1...Sf4
- 2.Rxf4#
- 1...Sh4
- 2.Rf4#
- 1...fxe5
- 2.Qxe5#
- 1...Se1
- Tries
- 1.Kb5?
- 1...fxe5
- 2.Qxe5#
- 1...Sf4
- 2.Rxf4#
- 1...Se1
- 2.Rf4#
- 1...Se3
- 2.Rf4#
- 1...Sh4
- 2.Rf4#
- 1...b6!
- 1...fxe5
- 1.Sc1?
- 1...Sf4
- 2.Rxf4#
- 1...Se1
- 2.Rf4#
- 1...Se3
- 2.Rf4#
- 1...Sh4
- 2.Rf4#
- 1...fxe5!
- 1...Sf4
- 1.Se1?
- 1...Sxe1
- 2.Rf4#
- 1...Sf4
- 2.Rxf4#
- 1...Se3
- 2.Rf4#
- 1...Sh4
- 2.Rf4#
- 1...fxe5!
- 1...Sxe1
- 1.Sb2?
- 1...Sf4
- 2.Rxf4#
- 1...Se1
- 2.Rf4#
- 1...Se3
- 2.Rf4#
- 1...Sh4
- 2.Rf4#
- 1...fxe5!
- 1...Sf4
- 1.Sb4?
- 1...Sf4
- 2.Rxf4#
- 1...Se1
- 2.Rf4#
- 1...Se3
- 2.Rf4#
- 1...Sh4
- 2.Rf4#
- 1...fxe5!
- 1...Sf4
- 1.Rxf2+?
- 1...Sf4
- 2.Rfxf4#
- 2.Rdxf4#
- 1...gxf2!
- 1...Sf4
- 1.Ra4?
- 1...Sf4
- 2.Rxf4#
- 1...Se1
- 2.Rf4#
- 1...Se3
- 2.Rf4#
- 1...Sh4
- 2.Rf4#
- 1...fxe5!
- 1...Sf4
- 1.Rb4?
- 1...Sf4
- 2.Rxf4#
- 1...Se1
- 2.Rf4#
- 1...Se3
- 2.Rf4#
- 1...Sh4
- 2.Rf4#
- 1...fxe5!
- 1...Sf4
- 1.Rc4?
- 1...Sf4
- 2.Rxf4#
- 1...Se1
- 2.Rf4#
- 1...Se3
- 2.Rf4#
- 1...Sh4
- 2.Rf4#
- 1...fxe5!
- 1...Sf4
- 1.Qxe7?
- threat
- 2.Qxf6#
- 2.Qh7#
- 1...fxe5
- 2.Qg5#
- 2.Qf8#
- 2.Qf7#
- 1...Sh4
- 2.Qxf6#
- 1...Sf4!
- threat
- 1.exf6+?
- 1...e5
- 2.Qxe5#
- 1...Kxf6!
- 1...e5
- 1.Kb5?
- Keys
- 1.Qc1!
- 1...fxe5
- 2.Qg5#
- 1...Sf4
- 2.Qxf4#
- 1...Se1
- 2.Qf4#
- 1...Se3
- 2.Rf4#
- 1...Sh4
- 2.Qf4#
- 1...fxe5
- 1.Qc1!
FEATURES
- Static
- TYPE = MUTATE
- CHANGED MATES = 4
- ADDED MATES = 0
- REMOVED MATES = 0
- Sets
- S(c);N_GUARD::R1(D)
- S(c);N_GUARD,N_SPINB(b)::R1(D),XS(c)
- P(g);OGATE,P_SPINP(g),XP(F)::QAR1(E),XP(g)
- Tries
- Try
- K(H);P-FLIGHT
- Vars
- P(g);OGATE,P_SPINP(g),XP(F)::QAR1(E),XP(g)
- S(c);N_GUARD,N_SPINB(b)::R1(D),XS(c)
- S(c);N_GUARD::R1(D)
- Refutation
- P(h);
- Try
- S(B);
- Vars
- S(c);N_GUARD,N_SPINB(b)::R1(D),XS(c)
- S(c);N_GUARD::R1(D)
- Refutation
- P(g);P_SPINP(g),XP(F)
- Try
- S(B);
- Vars
- S(c);N_GUARD,XS(B)::R1(D)
- S(c);N_GUARD,N_SPINB(b)::R1(D),XS(c)
- S(c);N_GUARD::R1(D)
- Refutation
- P(g);P_SPINP(g),XP(F)
- Try
- S(B);
- Vars
- S(c);N_GUARD,N_SPINB(b)::R1(D),XS(c)
- S(c);N_GUARD::R1(D)
- Refutation
- P(g);P_SPINP(g),XP(F)
- Try
- S(B);
- Vars
- S(c);N_GUARD,N_SPINB(b)::R1(D),XS(c)
- S(c);N_GUARD::R1(D)
- Refutation
- P(g);P_SPINP(g),XP(F)
- Try
- R(A);CHECK,XB(b)
- Refutation
- P(d);XR(A)
- Try
- R(D);P_SPINQ(E)
- Vars
- S(c);N_GUARD,N_SPINB(b)::R1(D),XS(c)
- S(c);N_GUARD::R1(D)
- S(c);N_GUARD,N_PINQ(E)::R1(D)
- Refutation
- P(g);P_SPINP(g),XP(F)
- Try
- R(D);P_SPINQ(E)
- Vars
- S(c);N_GUARD,N_SPINB(b)::R1(D),XS(c)
- S(c);N_GUARD::R1(D)
- S(c);N_GUARD,N_PINQ(E)::R1(D)
- Refutation
- P(g);P_SPINP(g),XP(F)
- Try
- R(D);P_SPINQ(E)
- Vars
- S(c);N_GUARD,N_SPINB(b)::R1(D),XS(c)
- S(c);N_GUARD::R1(D)
- S(c);N_GUARD,N_PINQ(E)::R1(D)
- Refutation
- P(g);P_SPINP(g),XP(F)
- Try
- Q(E);P_SPINR(D),XP(i)
- Threat
- DUALS(2)
- Vars
- S(c);::QAR1(E),XP(g)
- Refutation
- S(c);N_SPINB(b)
- Try
- P(F);CHECK,XP(g)
- Vars
- P(f);P_SPINP(f)::QAR1(E),XP(f)
- Refutation
- K(e);P-FLIGHT,XP(F)
- Try
- Actual
- Q(E);P_SPINR(D)
- Vars
- P(g);N_GUARD,XP(F)::QAR1(E)
- S(c);N_GUARD,N_SPINB(b)::QAR1(E),XS(c)
- S(c);N_GUARD::QAR1(E)
- S(c);N_PINR(D)::R1(D)
Developed and maintained by Brian Stephenson.
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