MESON Chess Problem Database

Problem Display
PID: 78652 (2r5/2pk1N2/q2p2p1/Br3pK1/B2N4/b6Q/1pR5/4R3 w - - 0 1)

Ling, John Francis

The Observer, 1943

(First published on Sun Sep 26 1943)

2r5/2pk1N2/q2p2p1/Br3pK1/B2N4/b6Q/1pR5/4R3

#2

8 + 10

136 Problem Observer 2008
15239 Valois Notebooks 2019

SOLUTION

  • SOUND
  • Sets
    • 1...Ra8
      • 2.Rxc7#
    • 1...Rb8
      • 2.Rxc7#
    • 1...Rd8
      • 2.Rxc7#
    • 1...Re8
      • 2.Rxc7#
    • 1...Rf8
      • 2.Rxc7#
    • 1...Rg8
      • 2.Rxc7#
    • 1...Rh8
      • 2.Rxc7#
  • Tries
    • 1.Kf6?
      • threat
        • 2.Re7#
      • 1...Ra8
        • 2.Rxc7#
      • 1...Rb8
        • 2.Rxc7#
      • 1...Rd8
        • 2.Rxc7#
      • 1...Re8
        • 2.Rxc7#
      • 1...Rf8
        • 2.Rxc7#
      • 1...Rg8
        • 2.Rxc7#
      • 1...Rh8
        • 2.Rxc7#
      • 1...d5+!
  • Keys
    • 1.Sxf5!
      • threat
        • 2.Re7#
      • 1...gxf5
        • 2.Qxf5#
      • 1...Ra8
        • 2.Rxc7#
      • 1...Rb8
        • 2.Rxc7#
      • 1...Rd8
        • 2.Rxc7#
      • 1...Re8
        • 2.Rxc7#
      • 1...Rf8
        • 2.Rxc7#
      • 1...Rg8
        • 2.Rxc7#
      • 1...Rh8
        • 2.Rxc7#
      • 1...Bc5
        • 2.Sd4#
      • 1...c5
        • 2.Sd4#
      • 1...d5
        • 2.S5d6#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 0
    • ADDED MATES = 4
    • REMOVED MATES = 0
  • Sets
    • R(j);N_GUARD::R1(B),XP(h)
  • Tries
    • Try
      • K(G);S_FLIGHT
      • Threat
        • R1(A)
      • Vars
        • R(j);N_GUARD::R1(B),XP(h)
        • R(j);N_GUARD,P_PINS(H)::R1(B),XP(h)
      • Refutation
        • P(f);CHECK
  • Actual
    • S(E);P_SPINS(E),XP(d)
    • Threat
      • R1(A)
    • Vars
      • P(g);OGATE,P_SPINP(g),XS(E)::QAB(C),XP(g)
      • R(j);N_GUARD::R1(B),XP(h)
      • B(b);N_PINS(E)::QAB(C)+S(E)
      • P(h);N_PINS(E)::QAB(C)+S(E)
      • P(f);N_PINS(E)::QAB(C)+S(E)
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