MESON Chess Problem Database
Problem Display
PID: 28308 (8/Q7/8/4p3/4P3/5RPK/4PN1b/R4rk1 w - - 0 1)
Penrose, Lionel Sharples
Reading Observer, 1917
#2
8 + 4
| 3242 | BCPS Rapid Solving (Cheltenham) | 2001 |
SOLUTION
- SOUND
- Sets
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3
- 2.Rxg3#
- 1...Rxa1
- Tries
- 1.Sd1+?
- 1...Rf2
- 2.Sb2#
- 2.Sxf2#
- 2.Sc3#
- 1...Kh1!
- 1...Rf2
- 1.Rb1?
- 1...Bxg3
- 2.Rxg3#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxb1!
- 1...Bxg3
- 1.Rc1?
- 1...Bxg3
- 2.Rxg3#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxc1!
- 1...Bxg3
- 1.Rd1?
- 1...Bxg3
- 2.Rxg3#
- 1...Re1
- 2.Rxe1#
- 1...Rxd1!
- 1...Bxg3
- 1.Re1?
- 1...Bxg3
- 2.Rxg3#
- 1...Rxe1!
- 1...Bxg3
- 1.Rb3?
- 1...Bxg3
- 2.Rxg3#
- 1...Rb1
- 2.Raxb1#
- 2.Rbxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxa1!
- 1...Bxg3
- 1.Rc3?
- 1...Bxg3
- 2.Rxg3#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Raxc1#
- 2.Rcxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxa1!
- 1...Bxg3
- 1.Rd3?
- 1...Bxg3
- 2.Rxg3#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Raxd1#
- 2.Rdxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxa1!
- 1...Bxg3
- 1.Rf5?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.Rf6?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.Rf7?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.Rf8?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.Qe3?
- 1...Bxg3
- 2.Rxg3#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 2.Qxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxa1!
- 1...Bxg3
- 1.Qd4?
- 1...Rxa1
- 2.Qxa1#
- 1...Bxg3
- 2.Rxg3#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 2.Qxd1#
- 1...Re1
- 2.Rxe1#
- 1...exd4!
- 1...Rxa1
- 1.Qc5?
- 1...Bxg3
- 2.Rxg3#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 2.Qxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxa1!
- 1...Bxg3
- 1.Qb6?
- 1...Bxg3
- 2.Rxg3#
- 1...Rb1
- 2.Rxb1#
- 2.Qxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxa1!
- 1...Bxg3
- 1.Qa2?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 2.Qxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.Qa3?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 2.Qxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.Qa4?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 2.Qxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.Qa5?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 2.Qxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.Qa6?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.Qf7?
- 1...Bxg3
- 2.Rxg3#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxa1!
- 1...Bxg3
- 1.Qg7?
- 1...Bxg3
- 2.Qxg3#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxa1!
- 1...Bxg3
- 1.Qa8?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.e3?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bxg3!
- 1...Rxa1
- 1.g4?
- 1...Rxa1
- 2.Qxa1#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Bg3
- 2.Rxg3#
- 1...Bf4!
- 1...Rxa1
- 1.Sd1+?
- Keys
- 1.Rfa3!
- 1...Rxa1
- 2.Rxa1#
- 1...Bxg3
- 2.Rxg3#
- 1...Rb1
- 2.Rxb1#
- 1...Rc1
- 2.Rxc1#
- 1...Rd1
- 2.Rxd1#
- 1...Re1
- 2.Rxe1#
- 1...Rxa1
- 1.Rfa3!
FEATURES
- Static
- TYPE = MUTATE
- CHANGED MATES = 1
- ADDED MATES = 0
- REMOVED MATES = 0
- Sets
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- B(c);OGATE,XP(E)::R(D),XB(c)
- Tries
- Try
- S(C);CHECK,N_PINR(a)
- Refutation
- K(b);P-FLIGHT
- Try
- R(A);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- R(A);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- R(A);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- R(A);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- R(D);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- R(D);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- R(D);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- R(D);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- R(D);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- R(D);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- R(D);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- Q(H);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- Q(H);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- P(d);XQ(H)
- Try
- Q(H);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- Q(H);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- Q(H);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- Q(H);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- Q(H);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- Q(H);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- Q(H);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- Q(H);
- Vars
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- Q(H);
- Vars
- B(c);OGATE,P_SPINB(c),XP(E)::QAR2(H),XB(c)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- R(a);N_SPINR(a),XR(A)
- Try
- Q(H);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- P(B);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- Refutation
- B(c);XP(E)
- Try
- P(E);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::QAR(H),XR(a)
- R(a);OGATEB::R(A),XR(a)
- B(c);N_GUARD::R(D),XB(c)
- Refutation
- B(c);
- Try
- Actual
- R(D);
- Vars
- R(a);N_SPINR(a),OGATE,XR(A)::R(D),XR(a)
- B(c);OGATE,XP(E)::R(D),XB(c)
- R(a);OGATEB::R(A),XR(a)
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Implemented with HTML5, MySQL, Perl (with, inter alia, CGI::Simple, HTML::Template & XML::LibXML) &
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