MESON Chess Problem Database

Problem Display
PID: 180835 (7k/prp1p3/3bB1K1/5p2/6p1/q4Q2/1R4N1/Br2R3 w - - 0 1)

Reeves, Alfred Christopher

The Observer, 1964

(First published on Sun Jan 19 1964)

7k/prp1p3/3bB1K1/5p2/6p1/q4Q2/1R4N1/Br2R3

#2

7 + 10

136 Problem Observer 2013

SOLUTION

  • SOUND
  • Sets
    • 1...Rxb2
      • 2.Qa8#
    • 1...Rb8
      • 2.Rxb8#
    • 1...g3
      • 2.Qh5#
  • Tries
    • 1.Rh1+?
      • 1...Bh2
        • 2.Rxh2#
      • 1...Rxh1!
    • 1.Qc6?
      • threat
        • 2.Qe8#
      • 1...Rb8
        • 2.Rxb8#
      • 1...Qa4!
    • 1.Qc3+?
      • 1...Be5
        • 2.Qxe5#
      • 1...Qxc3!
    • 1.Qxf5?
      • threat
        • 2.Qh5#
        • 2.Qf8#
      • 1...Qc5
        • 2.Qf8#
      • 1...Qe3
        • 2.Qf8#
      • 1...Qf3
        • 2.Qh5#
      • 1...Qh3
        • 2.Qf8#
      • 1...Qa5
        • 2.Qf8#
      • 1...Rb5
        • 2.Qf8#
      • 1...Rb8
        • 2.Rxb8#
        • 2.Qh5#
      • 1...Bf4
        • 2.Qf8#
      • 1...Qd3!
  • Keys
    • 1.Sf4!
      • threat
        • 2.Rh2#
      • 1...Qxb2
        • 2.Qh1#
      • 1...R1xb2
        • 2.Rh1#
      • 1...R7xb2
        • 2.Qa8#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 0
    • ADDED MATES = 2
    • REMOVED MATES = 2
  • Sets
    • R(g);OGATE,P_SPINR(g),XR(C)::QAB1(E)
    • R(g);OGATE::B(A)+R(C),DCHECK,XR(g)
    • P(c);OGATE::QAR(E)
  • Tries
    • Try
      • R(B);CHECK
      • Vars
        • B(e);N_GUARD,P_SPINB(e)::R(B),XB(e)
      • Refutation
        • R(a);XR(B)
    • Try
      • Q(E);
      • Threat
        • QAR(E)
      • Vars
        • R(g);OGATE::B(A)+R(C),DCHECK,XR(g)
      • Refutation
        • Q(b);
    • Try
      • Q(E);CHECK
      • Vars
        • B(e);N_GUARD,P_SPINB(e)::QAB(E),XB(e)
      • Refutation
        • Q(b);XQ(E)
    • Try
      • Q(E);XP(d)
      • Threat
        • DUALS(2)
      • Vars
        • Q(b);::QAR2(E)
        • Q(b);::QAR(E)
        • R(g);::QAR2(E)
        • B(e);::QAR2(E)
      • Refutation
        • Q(b);P_PINQ(E)
  • Actual
    • S(D);
    • Threat
      • B(A)+R(C),DCHECK
    • Vars
      • Q(b);N_GUARD,P_SPINQ(b),XR(C)::QAB(E)
      • R(a);N_GUARD,P_SPINR(a),XR(C)::R(B)
      • R(g);OGATE,P_SPINR(g),XR(C)::QAB1(E)
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