MESON Chess Problem Database

Problem Display
PID: 270770 (2R5/Q7/8/1PNpp3/K2k3r/bP2p3/1q2P3/B2N2R1 w - - 0 1)

Massingham, HW

The Observer, 1959

(First published on Sun Sep 6 1959)

2R5/Q7/8/1PNpp3/K2k3r/bP2p3/1q2P3/B2N2R1

#2

10 + 7

17397 Ling Notebooks 2023

SOLUTION

  • SOUND
  • Sets
    • 1...Qc3
      • 2.Bxc3#
    • 1...Re4
      • 2.Se6#
    • 1...e4
      • 2.Qg7#
  • Tries
    • 1.Sf2?
      • threat
        • 2.Se6#
      • 1...Kc3+
        • 2.Sce4#
      • 1...Bxc5
        • 2.Bxb2#
        • 2.Qxc5#
      • 1...e4
        • 2.Qg7#
      • 1...exf2!
    • 1.Rg4+?
      • 1...e4
        • 2.Qg7#
      • 1...Rxg4!
    • 1.Qh7?
      • threat
        • 2.Se6#
        • 2.Qd3#
      • 1...Bxc5
        • 2.Bxb2#
        • 2.Qd3#
      • 1...e4
        • 2.Qg7#
      • 1...Re4
        • 2.Se6#
      • 1...Rh6
        • 2.Qd3#
      • 1...Rxh7!
  • Keys
    • 1.Sc3!
      • threat
        • 2.Se6#
      • 1...Kxc3+
        • 2.Se4#
      • 1...Qxb3+
        • 2.Sxb3#
      • 1...Qxc3
        • 2.Rd1#
      • 1...Qxe2
        • 2.Sxe2#
      • 1...Bxc5
        • 2.Qxc5#
      • 1...e4
        • 2.Qg7#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 1
    • ADDED MATES = 4
    • REMOVED MATES = 1
  • Sets
    • Q(a);OGATE::B(A),XQ(a)
    • R(e);SBLOCK::QAB(I)+S(H),DCHECK
    • P(g);OGATEB::QAB(I)
  • Tries
    • Try
      • S(B);
      • Threat
        • QAB(I)+S(H),DCHECK
      • Vars
        • K(d);CHECK,S_FLIGHT::R(J)+S(H),DCHECK
        • P(g);OGATEB::QAB(I)
      • Refutation
        • P(c);XS(B)
    • Try
      • R(C);CHECK
      • Vars
        • P(g);P_SPINP(g),S_CUTR(e)::QAB(I)
      • Refutation
        • R(e);XR(C)
    • Try
      • Q(I);
      • Threat
        • DUALS(2)
      • Vars
        • P(g);OGATEB::QAB(I)
        • R(e);::S(H)
        • R(e);::QAR1(I)
      • Refutation
        • R(e);XQ(I)
  • Actual
    • S(B);N_PINQ(a)
    • Threat
      • QAB(I)+S(H),DCHECK
    • Vars
      • K(d);CHECK,P_SPINQ(a),S_FLIGHT,XS(B)::R(J)+S(H),DCHECK
      • Q(a);CHECK,XP(E)::QAB(I)+S(H),DCHECK,XQ(a)
      • Q(a);N_GUARD,P_SPINQ(a),XS(B)::R(C)
      • Q(a);XP(D)::B(A)+S(B),DCHECK,XQ(a)
      • B(b);OGATE,P_SPINB(b),XS(H)::QAB1(I),XB(b)
      • P(g);OGATEB::QAB(I)
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