MESON Chess Problem Database

Problem Display
PID: 80601 (8/8/4p3/4P3/2p2QN1/2P2Bp1/nKN1P3/2nk4 w - - 0 1)

Penrose, Lionel Sharples

The Field, 1947

(First published on Sat May 24 1947)

8/8/4p3/4P3/2p2QN1/2P2Bp1/nKN1P3/2nk4

#2

8 + 6

SOLUTION

  • SOUND
  • Sets
    • 1...Sxe2
      • 2.Qd4#
    • 1...Sb3
      • 2.e4#
    • 1...Sd3+
      • 2.exd3#
    • 1...Sxc3
      • 2.Qxc1#
    • 1...Sb4
      • 2.Qxc1#
    • 1...g2
      • 2.Sf2#
  • Tries
    • 1.Kb1?
      • 1...Sxe2
        • 2.Qd4#
      • 1...Sb3
        • 2.e4#
      • 1...Sd3
        • 2.exd3#
        • 2.e4#
      • 1...Sb4
        • 2.Qxc1#
      • 1...g2
        • 2.Sf2#
      • 1...Sxc3+!
    • 1.Sf6?
      • 1...Sd3+
        • 2.exd3#
      • 1...Sxe2
        • 2.Qd4#
      • 1...Sxc3
        • 2.Qxc1#
      • 1...Sb3
        • 2.e4#
      • 1...Sb4
        • 2.Qxc1#
      • 1...g2!
    • 1.Sh6?
      • 1...Sd3+
        • 2.exd3#
      • 1...Sxe2
        • 2.Qd4#
      • 1...Sxc3
        • 2.Qxc1#
      • 1...Sb3
        • 2.e4#
      • 1...Sb4
        • 2.Qxc1#
      • 1...g2!
    • 1.Qe3?
      • 1...Sd3+
        • 2.exd3#
      • 1...Sxe2
        • 2.Bxe2#
        • 2.Qd4#
        • 2.Qxe2#
      • 1...Sxc3
        • 2.Qxc1#
      • 1...g2
        • 2.Sf2#
      • 1...Sb4
        • 2.Qxc1#
      • 1...Sb3!
    • 1.Qxg3?
      • threat
        • 2.Qe1#
      • 1...Kd2
        • 2.Qe1#
      • 1...Sd3+!
    • 1.Qh6?
      • 1...Sd3+
        • 2.exd3#
      • 1...Sxc3
        • 2.Qxc1#
      • 1...g2
        • 2.Sf2#
      • 1...Sb3
        • 2.e4#
      • 1...Sb4
        • 2.Qxc1#
      • 1...Sxe2!
    • 1.e3+?
      • 1...Se2
        • 2.Qd4#
      • 1...Kd2!
  • Keys
    • 1.Qg5!
      • 1...Sd3+
        • 2.exd3#
      • 1...Sxe2
        • 2.Qd8#
      • 1...Sxc3
        • 2.Qxc1#
      • 1...g2
        • 2.Sf2#
      • 1...Sb3
        • 2.e4#
      • 1...Sb4
        • 2.Qxc1#

FEATURES

  • Static
    • TYPE = MUTATE
    • CHANGED MATES = 1
    • ADDED MATES = 0
    • REMOVED MATES = 0
  • Sets
    • S(a);N_GUARD,P_SPINS(a),XP(C)::QAR(F)
    • S(a);N_GUARD::B(E)+P(C)
    • S(a);CHECK,OGATE::B(E)+P(C),XS(a)
    • S(c);N_GUARD,XP(D)::QAR1(F),XS(a)
    • S(c);N_GUARD::QAR1(F),XS(a)
    • P(d);N_GUARD::S(G)
  • Tries
    • Try
      • K(A);P-FLIGHT
      • Vars
        • S(a);N_GUARD,P_SPINS(a),XP(C)::QAR(F)
        • S(a);N_GUARD::B(E)+P(C)
        • S(c);N_GUARD::QAR1(F),XS(a)
        • P(d);N_GUARD::S(G)
      • Refutation
        • S(c);CHECK,XP(D)
    • Try
      • S(G);
      • Vars
        • S(a);CHECK,OGATE::B(E)+P(C),XS(a)
        • S(a);N_GUARD,P_SPINS(a),XP(C)::QAR(F)
        • S(c);N_GUARD,XP(D)::QAR1(F),XS(a)
        • S(a);N_GUARD::B(E)+P(C)
        • S(c);N_GUARD::QAR1(F),XS(a)
      • Refutation
        • P(d);
    • Try
      • S(G);
      • Vars
        • S(a);CHECK,OGATE::B(E)+P(C),XS(a)
        • S(a);N_GUARD,P_SPINS(a),XP(C)::QAR(F)
        • S(c);N_GUARD,XP(D)::QAR1(F),XS(a)
        • S(a);N_GUARD::B(E)+P(C)
        • S(c);N_GUARD::QAR1(F),XS(a)
      • Refutation
        • P(d);
    • Try
      • Q(F);
      • Vars
        • S(a);CHECK,OGATE::B(E)+P(C),XS(a)
        • S(c);N_GUARD,XP(D)::QAR1(F),XS(a)
        • P(d);N_GUARD::S(G)
        • S(c);N_GUARD::QAR1(F),XS(a)
      • Refutation
        • S(a);
    • Try
      • Q(F);XP(d)
      • Threat
        • QAR1(F)
      • Vars
        • K(b);P-FLIGHT::QAB1(F)
      • Refutation
        • S(a);CHECK
    • Try
      • Q(F);
      • Vars
        • S(a);CHECK,OGATE::B(E)+P(C),XS(a)
        • S(c);N_GUARD,XP(D)::QAR1(F),XS(a)
        • P(d);N_GUARD::S(G)
        • S(a);N_GUARD::B(E)+P(C)
        • S(c);N_GUARD::QAR1(F),XS(a)
      • Refutation
        • S(a);P_SPINS(a),XP(C)
    • Try
      • P(C);CHECK
      • Vars
        • S(a);P_SPINS(a)::QAR(F)
      • Refutation
        • K(b);P-FLIGHT
  • Actual
    • Q(F);
    • Vars
      • S(a);CHECK,OGATE::B(E)+P(C),XS(a)
      • S(a);N_GUARD,P_SPINS(a),XP(C)::QAB(F)
      • S(c);N_GUARD,XP(D)::QAR1(F),XS(a)
      • P(d);N_GUARD::S(G)
      • S(a);N_GUARD::B(E)+P(C)
      • S(c);N_GUARD::QAR1(F),XS(a)
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