MESON Chess Problem Database
Problem Display
PID: 143522 (3R4/2p4p/N2q1b1Q/pB1n4/3k4/r1N1RP2/p4B2/K2b4 w - - 0 1)
Lubell, Martin S
American Chess Problemist, 1949
#2
9 + 10
SOLUTION
- SOUND
- Sets
- 1...Qh2
- 2.Rxd5#
- 1...Qg3
- 2.Rxd5#
- 1...Qb4
- 2.Rxd5#
- 2.Qf4#
- 2.Qxf6#
- 1...Qf4
- 2.Rxd5#
- 2.Qxf4#
- 1...Qc5
- 2.Qf4#
- 2.Qxf6#
- 1...Qe5
- 2.Rd3#
- 1...Qe7
- 2.Rxd5#
- 1...Qf8
- 2.Rxd5#
- 2.Qf4#
- 1...Qxa6
- 2.Rxd5#
- 1...Qb6
- 2.Rxd5#
- 2.Qf4#
- 1...Qc6
- 2.Qf4#
- 1...Rxc3
- 2.Re4#
- 1...Bc2
- 2.Se2#
- 1...Be2
- 2.Sxe2#
- 1...Bb3
- 2.Se2#
- 1...Ba4
- 2.Se2#
- 1...Be5
- 2.Rd3#
- 1...Sxe3
- 2.Qxe3#
- 2.Qxf6#
- 1...Sb4
- 2.Qf4#
- 2.Qxf6#
- 1...Sf4
- 2.Qxf4#
- 2.Qxf6#
- 1...Sb6
- 2.Qf4#
- 2.Qxf6#
- 1...Se7
- 2.Qf4#
- 2.Qxf6#
- 1...Qh2
- Tries
- 1.Re1+?
- 1...Se3
- 2.Qxe3#
- 2.Qxf6#
- 1...Kxc3!
- 1...Se3
- 1.Re2+?
- 1...Se3
- 2.Qxe3#
- 2.Qxf6#
- 1...Kxc3!
- 1...Se3
- 1.Re6+?
- 1...Se3
- 2.Qxe3#
- 2.Qxf6#
- 1...Kxc3!
- 1...Se3
- 1.Re7+?
- 1...Se3
- 2.Qxe3#
- 2.Qxf6#
- 1...Kxc3!
- 1...Se3
- 1.Ree8+?
- 1...Se3
- 2.Qxe3#
- 2.Qxf6#
- 1...Kxc3!
- 1...Se3
- 1.Rxd6?
- threat
- 2.Rxd5#
- 2.Qf4#
- 2.Qxf6#
- 1...Rxc3
- 2.Re4#
- 2.Qf4#
- 2.Qxf6#
- 1...Bxf3
- 2.Qxf6#
- 1...Bc2
- 2.Se2#
- 2.Rxd5#
- 2.Qxf6#
- 1...Bb3
- 2.Se2#
- 2.Qf4#
- 2.Qxf6#
- 1...Bh4
- 2.Rxd5#
- 2.Qf4#
- 2.Qxh4#
- 1...Be5
- 2.Rd3#
- 2.Rxd5#
- 1...Bg5
- 2.Rxd5#
- 1...Be7
- 2.Rxd5#
- 2.Qf4#
- 1...Bg7
- 2.Rxd5#
- 2.Qf4#
- 2.Qxg7#
- 2.Qh4#
- 1...Bd8
- 2.Rxd5#
- 2.Qf4#
- 1...Bh8
- 2.Rxd5#
- 2.Qf4#
- 2.Qh4#
- 1...c6
- 2.Qf4#
- 2.Qxf6#
- 1...cxd6!
- threat
- 1.Qf4+?
- 1...Qxf4
- 2.Rxd5#
- 1...Sxf4!
- 1...Qxf4
- 1.Qg5?
- threat
- 2.Rd3#
- 1...Sxe3
- 2.Qxe3#
- 2.Qxf6#
- 2.Qc5#
- 1...Bxg5!
- threat
- 1.Qh2?
- threat
- 2.Rd3#
- 1...Qxh2
- 2.Rxd5#
- 1...Qg3
- 2.Rxd5#
- 1...Qf4
- 2.Rxd5#
- 2.Qxf4#
- 1...Sf4
- 2.Qxf4#
- 1...Sxe3!
- threat
- 1.Qh4+?
- 1...Qf4
- 2.Rxd5#
- 2.Qxf4#
- 1...Sf4
- 2.Qxf6#
- 2.Qxf4#
- 1...Bxh4!
- 1...Qf4
- 1.Qh5?
- threat
- 2.Rd3#
- 1...Sxe3
- 2.Qc5#
- 1...Bg5!
- threat
- 1.Qxf6+?
- 1...Qe5
- 2.Rd3#
- 2.Rxd5#
- 2.Qxe5#
- 1...Qxf6
- 2.Rxd5#
- 1...Sxf6!
- 1...Qe5
- 1.Qg6?
- threat
- 2.Qd3#
- 2.Qe4#
- 1...Qxa6
- 2.Rxd5#
- 1...Rxc3
- 2.Re4#
- 2.Qe4#
- 1...Bxf3
- 2.Qd3#
- 1...Sxc3
- 2.Qd3#
- 1...Sxe3
- 2.Qxf6#
- 1...Qf4
- 2.Rxd5#
- 2.Qd3#
- 1...Qe5
- 2.Rd3#
- 2.Qd3#
- 1...Qe7
- 2.Rxd5#
- 2.Qd3#
- 1...Qe6
- 2.Qd3#
- 1...Bc2
- 2.Se2#
- 1...Be2
- 2.Sxe2#
- 2.Qe4#
- 1...Sb4
- 2.Qe4#
- 2.Qg4#
- 2.Qxf6#
- 1...Sf4
- 2.Qe4#
- 2.Qxf6#
- 1...hxg6!
- threat
- 1.Qxh7?
- threat
- 2.Qd3#
- 2.Qe4#
- 1...Qxa6
- 2.Rxd5#
- 1...Rxc3
- 2.Re4#
- 2.Qe4#
- 1...Bxf3
- 2.Qd3#
- 1...Sxc3
- 2.Qd3#
- 1...Qf4
- 2.Rxd5#
- 2.Qd3#
- 1...Qe5
- 2.Rd3#
- 2.Qd3#
- 1...Qe7
- 2.Rxd5#
- 2.Qd3#
- 1...Qe6
- 2.Qd3#
- 1...Bc2
- 2.Se2#
- 1...Be2
- 2.Sxe2#
- 2.Qe4#
- 1...Sb4
- 2.Qe4#
- 1...Sf4
- 2.Qe4#
- 1...Sxe3!
- threat
- 1.f4?
- threat
- 2.Rd3#
- 1...Qxf4
- 2.Rxd5#
- 2.Qxf4#
- 1...Sxc3
- 2.Re5#
- 1...Sxe3
- 2.Qxf6#
- 1...Sxf4
- 2.Qxf4#
- 2.Qxf6#
- 1...Rxc3!
- threat
- 1.Re1+?
- Keys
- 1.Bg3!
- threat
- 2.Rd3#
- 1...Qxg3
- 2.Rxd5#
- 1...Qxa6
- 2.Rxd5#
- 1...Rxc3
- 2.Re4#
- 1...Sxe3
- 2.Qxf6#
- 1...Qf4
- 2.Qxf4#
- 1...Sf4
- 2.Qxf4#
- 1...Bc2
- 2.Se2#
- 1...Be2
- 2.Sxe2#
- 1...Sb4
- 2.Qf4#
- threat
- 1.Bg3!
FEATURES
- Static
- TYPE = THREAT
- CHANGED MATES = 0
- ADDED MATES = 4
- REMOVED MATES = 7
- Sets
- Q(g);OGATE,P_SPINS(f)::R1(I),XS(f)
- Q(g);P_SPINS(f),SBLOCK::B(B)+R(D),DCHECK
- Q(g);OGATE,P_SPINS(f),XS(G)::R1(I),XS(f)
- Q(g);N_GUARD,P_SPINS(f)::QAR2(H)
- R(c);SBLOCK,XS(C)::B(B)+R(D),DCHECK
- B(a);N_GUARD::S(C)
- B(a);N_GUARD::S(C),XB(a)
- B(h);SBLOCK::B(B)+R(D),DCHECK
- Tries
- Try
- R(D);CHECK
- Refutation
- K(d);S_FLIGHT,XS(C)
- Try
- R(D);CHECK
- Refutation
- K(d);S_FLIGHT,XS(C)
- Try
- R(D);CHECK
- Refutation
- K(d);S_FLIGHT,XS(C)
- Try
- R(D);CHECK
- Refutation
- K(d);S_FLIGHT,XS(C)
- Try
- R(D);CHECK
- Refutation
- K(d);S_FLIGHT,XS(C)
- Try
- R(I);P_PINS(f),XQ(g)
- Threat
- DUALS(3)
- Vars
- B(a);XP(E)::QAB(H),XB(h)
- B(h);::R1(I),XS(f)
- Refutation
- P(i);N_SPINS(f),XR(I)
- Try
- Q(H);CHECK
- Vars
- Q(g);OGATE,P_SPINS(f),XQ(H)::R1(I),XS(f)
- Refutation
- S(f);P_SPINQ(g),XQ(H)
- Try
- Q(H);
- Threat
- B(B)+R(D),DCHECK
- Refutation
- B(h);XQ(H)
- Try
- Q(H);
- Threat
- B(B)+R(D),DCHECK
- Vars
- Q(g);OGATE,P_SPINS(f),XQ(H)::R1(I),XS(f)
- Q(g);OGATE,P_SPINS(f)::R1(I),XS(f)
- S(f);N_GUARD,P_SPINQ(g)::QAR2(H),XS(f)
- Refutation
- S(f);P_SPINQ(g),P_SPINS(f),XR(D)
- Try
- Q(H);CHECK
- Refutation
- B(h);XQ(H)
- Try
- Q(H);
- Threat
- B(B)+R(D),DCHECK
- Vars
- S(f);OGATE,P_SPINQ(g),P_SPINS(f),XR(D)::QAB1(H)
- Refutation
- B(h);
- Try
- Q(H);CHECK,XB(h)
- Vars
- Q(g);OGATE,P_SPINS(f),XQ(H)::R1(I),XS(f)
- Refutation
- S(f);P_SPINQ(g),XQ(H)
- Try
- Q(H);
- Threat
- DUALS(2)
- Vars
- Q(g);OGATE,P_SPINS(f),XS(G)::R1(I),XS(f)
- B(a);XP(E)::QAR1(H)
- S(f);P_SPINQ(g),XS(C)::QAR1(H)
- S(f);N_GUARD,P_SPINQ(g),P_SPINS(f),XR(D)::QAB(H),XB(h)
- Q(g);P_SPINS(f)::QAR1(H)
- B(a);N_GUARD::S(C)
- Refutation
- P(j);XQ(H)
- Try
- Q(H);XP(j)
- Threat
- DUALS(2)
- Vars
- Q(g);OGATE,P_SPINS(f),XS(G)::R1(I),XS(f)
- B(a);XP(E)::QAR1(H)
- S(f);P_SPINQ(g),XS(C)::QAR1(H)
- Q(g);P_SPINS(f)::QAR1(H)
- B(a);N_GUARD::S(C)
- S(f);P_SPINQ(g)::QAR1(H)
- Refutation
- S(f);P_SPINQ(g),P_SPINS(f),XR(D)
- Try
- P(E);
- Threat
- B(B)+R(D),DCHECK
- Vars
- S(f);N_GUARD,P_SPINQ(g),SBLOCK,XS(C)::B(B)+R(D)
- S(f);N_GUARD,P_SPINQ(g),P_SPINS(f),XR(D)::QAB(H),XB(h)
- Refutation
- R(c);XS(C)
- Try
- Actual
- B(B);
- Threat
- R1(D)
- Vars
- Q(g);OGATE,P_SPINS(f),XB(B)::R1(I),XS(f)
- Q(g);OGATE,P_SPINS(f),XS(G)::R1(I),XS(f)
- R(c);SBLOCK,XS(C)::R1(D)
- S(f);N_GUARD,P_SPINQ(g),SBLOCK,XR(D)::QAB(H),XB(h)
- Q(g);N_GUARD,P_SPINS(f)::QAR2(H),XQ(g)
- S(f);N_GUARD,P_SPINQ(g)::QAR2(H),XS(f)
- B(a);N_GUARD::S(C)
- B(a);N_GUARD::S(C),XB(a)
- S(f);N_GUARD,P_SPINQ(g)::QAR2(H)
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