MESON Chess Problem Database
Problem Display
PID: 267069 (8/1Q6/1p1PN3/pP1rPp1n/Rb1Bk1N1/p2R2p1/P3P1n1/3K4 w - - 0 1)
Penrose, Lionel Sharples
The Problemist, 1955
#2
12 + 10
SOLUTION
- SOUND
- Sets
- 1...Be1
- 2.Bc3#
- 1...Bd2
- 2.Bc3#
- 1...Bc3
- 2.Bxc3#
- 1...Bc5
- 2.Bxc5#
- 1...Bxd6
- 2.Bc5#
- 1...Se1
- 2.Re3#
- 1...Se3+
- 2.Rxe3#
- 1...Sgf4
- 2.Sg5#
- 2.Re3#
- 1...Sh4
- 2.Re3#
- 1...Shf4
- 2.Sf6#
- 2.Sg5#
- 1...Sf6
- 2.Sxf6#
- 1...Sg7
- 2.Sf6#
- 1...fxg4
- 2.Qh7#
- 1...f4
- 2.Qh7#
- 1...Be1
- Tries
- 1.Kc1?
- 1...Bxd6
- 2.Bc5#
- 1...fxg4
- 2.Qh7#
- 1...f4
- 2.Qh7#
- 1...Be1
- 2.Bc3#
- 1...Bc3
- 2.Bxc3#
- 1...Bc5
- 2.Bxc5#
- 1...Se1
- 2.Re3#
- 1...Se3
- 2.Rxe3#
- 1...Sgf4
- 2.Sg5#
- 2.Re3#
- 1...Sh4
- 2.Re3#
- 1...Shf4
- 2.Sf6#
- 2.Sg5#
- 1...Sf6
- 2.Sxf6#
- 1...Sg7
- 2.Sf6#
- 1...Bd2+!
- 1...Bxd6
- 1.Kc2?
- 1...Se3+
- 2.Rxe3#
- 1...Bxd6
- 2.Bc5#
- 1...fxg4
- 2.Qh7#
- 1...f4
- 2.Qh7#
- 1...Be1
- 2.Bc3#
- 1...Bd2
- 2.Bc3#
- 1...Bc3
- 2.Bxc3#
- 1...Bc5
- 2.Bxc5#
- 1...Sgf4
- 2.Sg5#
- 2.Re3#
- 1...Sh4
- 2.Re3#
- 1...Shf4
- 2.Sf6#
- 2.Sg5#
- 1...Sf6
- 2.Sxf6#
- 1...Sg7
- 2.Sf6#
- 1...Se1+!
- 1...Se3+
- 1.Se3?
- threat
- 2.Qxd5#
- 1...Sxe3+
- 2.Rxe3#
- 1...Sgf4
- 2.Sg5#
- 1...Shf4
- 2.Sg5#
- 1...Sf6!
- threat
- 1.Ba1?
- threat
- 2.Rd4#
- 2.Qxd5#
- 1...fxg4
- 2.Qh7#
- 1...f4
- 2.Qh7#
- 1...Sgf4
- 2.Sg5#
- 2.Rd4#
- 1...Shf4
- 2.Sf6#
- 2.Sg5#
- 2.Rd4#
- 1...Sf6
- 2.Sxf6#
- 2.Rd4#
- 1...Se3+!
- threat
- 1.Bb2?
- threat
- 2.Rd4#
- 2.Qxd5#
- 1...fxg4
- 2.Qh7#
- 1...f4
- 2.Qh7#
- 1...Sgf4
- 2.Sg5#
- 2.Rd4#
- 1...Shf4
- 2.Sf6#
- 2.Sg5#
- 2.Rd4#
- 1...Sf6
- 2.Sxf6#
- 2.Rd4#
- 1...Se3+!
- threat
- 1.Bc3?
- threat
- 2.Rd4#
- 2.Qxd5#
- 1...fxg4
- 2.Qh7#
- 1...f4
- 2.Qh7#
- 1...Sgf4
- 2.Sg5#
- 2.Rd4#
- 1...Shf4
- 2.Sf6#
- 2.Sg5#
- 2.Rd4#
- 1...Sf6
- 2.Sxf6#
- 2.Rd4#
- 1...Se3+!
- threat
- 1.Rxg3?
- threat
- 2.Sf2#
- 1...Se3+
- 2.Rxe3#
- 1...fxg4
- 2.Qh7#
- 1...f4
- 2.Qh7#
- 1...Be1!
- threat
- 1.Rxb4?
- 1...Se3+
- 2.Rxe3#
- 1...fxg4
- 2.Qh7#
- 1...f4
- 2.Qh7#
- 1...Se1
- 2.Re3#
- 1...Sgf4
- 2.Sg5#
- 2.Re3#
- 1...Sh4
- 2.Re3#
- 1...Shf4
- 2.Sf6#
- 2.Sg5#
- 1...Sf6
- 2.Sxf6#
- 1...Sg7
- 2.Sf6#
- 1...a4
- 2.Ba1#
- 2.Bg1#
- 2.Bb2#
- 2.Bf2#
- 2.Bc3#
- 2.Be3#
- 2.Bc5#
- 2.Bxb6#
- 1...axb4!
- 1...Se3+
- 1.Kc1?
- Keys
- 1.Rf3!
- 1...Se3+
- 2.Rxe3#
- 1...Bxd6
- 2.Sg5#
- 1...fxg4
- 2.Qh7#
- 1...f4
- 2.Qh7#
- 1...Be1
- 2.Sg5#
- 1...Bd2
- 2.Bc3#
- 1...Bc3
- 2.Sg5#
- 1...Bc5
- 2.Sg5#
- 1...Se1
- 2.Re3#
- 1...Sgf4
- 2.Re3#
- 1...Sh4
- 2.Re3#
- 1...Shf4
- 2.Sf6#
- 1...Sf6
- 2.Sxf6#
- 1...Sg7
- 2.Sf6#
- 1...Se3+
- 1.Rf3!
FEATURES
- Static
- TYPE = MUTATE
- CHANGED MATES = 4
- ADDED MATES = 2
- REMOVED MATES = 0
- Sets
- B(d);OGATEB::R(E)+B(F)
- B(d);OGATEB::R(E)+B(F),XB(d)
- B(d);OGATEB,XP(J)::R(E)+B(F)
- S(a);N_GUARD::R1(D)
- S(a);CHECK,N_GUARD::R1(D),XS(a)
- S(i);N_GUARD::S(G),XS(i)
- S(i);N_GUARD::S(G)
- P(h);OGATEB,XS(G)::QAB(L)
- P(h);OGATEB::QAB(L)
- Tries
- Try
- K(A);P-FLIGHT
- Vars
- B(d);OGATEB,XP(J)::R(E)+B(F)
- P(h);OGATEB,XS(G)::QAB(L)
- P(h);OGATEB::QAB(L)
- B(d);OGATEB::R(E)+B(F)
- B(d);OGATEB::R(E)+B(F),XB(d)
- S(a);N_GUARD::R1(D)
- S(a);N_GUARD::R1(D),XS(a)
- S(i);N_GUARD::S(G),XS(i)
- S(i);N_GUARD::S(G)
- Refutation
- B(d);CHECK
- Try
- K(A);S_FLIGHT
- Vars
- S(a);CHECK,N_GUARD::R1(D),XS(a)
- B(d);OGATEB,XP(J)::R(E)+B(F)
- P(h);OGATEB,XS(G)::QAB(L)
- P(h);OGATEB::QAB(L)
- B(d);OGATEB::R(E)+B(F)
- B(d);OGATEB::R(E)+B(F),XB(d)
- S(a);N_GUARD::R1(D)
- S(i);N_GUARD::S(G),XS(i)
- S(i);N_GUARD::S(G)
- Refutation
- S(a);CHECK
- Try
- S(G);
- Threat
- QAB1(L),XR(g)
- Vars
- S(a);CHECK,OGATE,XS(G)::R1(D),XS(a)
- S(a);SBLOCK::S(K)
- S(i);SBLOCK::S(K)
- Refutation
- S(i);
- Try
- B(F);P_PINB(d),P_SPINR(D)
- Threat
- DUALS(2)
- Vars
- P(h);OGATEB,XS(G)::QAB(L)
- P(h);OGATEB::QAB(L)
- Refutation
- S(a);CHECK
- Try
- B(F);P_PINB(d),P_SPINR(D)
- Threat
- DUALS(2)
- Vars
- P(h);OGATEB,XS(G)::QAB(L)
- P(h);OGATEB::QAB(L)
- Refutation
- S(a);CHECK
- Try
- B(F);P_PINB(d),P_SPINR(D)
- Threat
- DUALS(2)
- Vars
- P(h);OGATEB,XS(G)::QAB(L)
- P(h);OGATEB::QAB(L)
- Refutation
- S(a);CHECK
- Try
- R(D);P_SPINB(F),XP(c)
- Threat
- S(G)
- Vars
- S(a);CHECK,N_GUARD::R1(D),XS(a)
- P(h);OGATEB,XS(G)::QAB(L)
- P(h);OGATEB::QAB(L)
- Refutation
- B(d);
- Try
- R(E);XB(d)
- Vars
- S(a);CHECK,N_GUARD::R1(D),XS(a)
- P(h);OGATEB,XS(G)::QAB(L)
- P(h);OGATEB::QAB(L)
- S(a);N_GUARD::R1(D)
- S(i);N_GUARD::S(G),XS(i)
- S(i);N_GUARD::S(G)
- Refutation
- P(f);XR(E)
- Try
- Actual
- R(D);P_SPINB(F)
- Vars
- S(a);CHECK,N_GUARD::R1(D),XS(a)
- B(d);XP(J)::S(K)
- P(h);OGATEB,XS(G)::QAB(L)
- P(h);OGATEB::QAB(L)
- B(d);::S(K)
- B(d);N_PINB(F)::R(E)+B(F)
- S(a);N_GUARD::R1(D)
- S(i);N_GUARD::S(G)
- S(i);N_GUARD::S(G),XS(i)
Developed and maintained by Brian Stephenson.
Implemented with HTML5, MySQL, Perl (with, inter alia, CGI::Simple, HTML::Template & XML::LibXML) &
CSS/Javascript (jQuery, Bootstrap & DataTables).