MESON Chess Problem Database

Problem Display
PID: 164769 (7q/3N4/6n1/5pp1/2P1k1p1/2P1PR2/2K1Q3/3N3n w - - 0 1)

Meurs, Abraham

The Observer, 1926

(First published on Sun Oct 31 1926)

7q/3N4/6n1/5pp1/2P1k1p1/2P1PR2/2K1Q3/3N3n

#2

8 + 7

15239 Valois Notebooks 2017

SOLUTION

  • SOUND
  • Sets
    • 1...Qxc3+
      • 2.Sxc3#
    • 1...Qd4
      • 2.exd4#
    • 1...Sf2
      • 2.Sxf2#
    • 1...Sg3
      • 2.Sf2#
    • 1...Sf4
      • 2.exf4#
    • 1...Se5
      • 2.Sc5#
    • 1...gxf3
      • 2.Qd3#
  • Tries
    • 1.Rf1?
      • threat
        • 2.Qd3#
        • 2.Qg2#
      • 1...Qxc3+
        • 2.Sxc3#
      • 1...f4
        • 2.Qd3#
      • 1...Qd4
        • 2.Qg2#
        • 2.exd4#
      • 1...Qh3
        • 2.Qd3#
      • 1...Sf2
        • 2.Sxf2#
      • 1...Sf4
        • 2.exf4#
      • 1...Sh4
        • 2.Qd3#
      • 1...Se5
        • 2.Sc5#
      • 1...Qh2!
    • 1.Qg2?
      • threat
        • 2.Rf1#
        • 2.Rf2#
        • 2.Rg3#
        • 2.Rh3#
        • 2.Rf4#
      • 1...Qxc3+
        • 2.Sxc3#
      • 1...f4
        • 2.Rxf4#
      • 1...Qh2
        • 2.Rf4#
      • 1...Qh3
        • 2.Rxh3#
        • 2.Rf4#
      • 1...Sf2
        • 2.Sxf2#
        • 2.Rxf2#
        • 2.Rg3#
        • 2.Rh3#
        • 2.Rf4#
      • 1...Sg3
        • 2.Sf2#
        • 2.Rf1#
        • 2.Rf2#
        • 2.Rxg3#
        • 2.Rf4#
      • 1...Sf4
        • 2.Rxf4#
      • 1...Sh4
        • 2.Rf4#
      • 1...Se5
        • 2.Sc5#
        • 2.Rf4#
      • 1...g3
        • 2.Rf1#
        • 2.Rf2#
        • 2.Rxg3#
        • 2.Rf4#
      • 1...gxf3!
  • Keys
    • 1.Rf2!
      • threat
        • 2.Qd3#
      • 1...Qxc3+
        • 2.Sxc3#
      • 1...Sxf2
        • 2.Sxf2#
      • 1...Qd4
        • 2.exd4#
      • 1...Sf4
        • 2.exf4#
      • 1...Se5
        • 2.Sc5#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 0
    • ADDED MATES = 0
    • REMOVED MATES = 2
  • Sets
    • Q(g);CHECK,XP(D)::S(A),XQ(g)
    • Q(g);OGATE::QAR(C)+P(E),XQ(g)
    • S(a);N_GUARD::S(A),XS(a)
    • S(a);N_GUARD::S(A)
    • S(f);OGATE::QAR(C)+P(E),XS(f)
    • S(f);SBLOCK::S(H)
    • P(c);SBLOCK,XR(F)::QAB1(C)
  • Tries
    • Try
      • R(F);
      • Threat
        • DUALS(2)
      • Vars
        • Q(g);CHECK,XP(D)::S(A),XQ(g)
        • P(d);::QAB1(C)
        • Q(g);::QAB1(C)
        • S(a);N_GUARD::S(A),XS(a)
        • S(f);OGATE::QAR(C)+P(E),XS(f)
        • S(f);::QAB1(C)
        • S(f);SBLOCK::S(H)
      • Refutation
        • Q(g);P_PINQ(C)
    • Try
      • Q(C);
      • Threat
        • DUALS(5)
      • Vars
        • Q(g);CHECK,XP(D)::S(A),XQ(g)
        • P(d);::QAB(C)+R(F),DCHECK,XP(d)
        • Q(g);P_PINQ(C)::QAB(C)+R(F),DCHECK
        • S(f);::QAB(C)+R(F),DCHECK,XS(f)
        • S(f);::QAB(C)+R(F),DCHECK
      • Refutation
        • P(c);P_SPINP(c),XR(F)
  • Actual
    • R(F);
    • Threat
      • QAB1(C)
    • Vars
      • Q(g);CHECK,XP(D)::S(A),XQ(g)
      • S(a);XR(F)::S(A),XS(a)
      • Q(g);OGATE::QAR(C)+P(E),XQ(g)
      • S(f);OGATE::QAR(C)+P(E),XS(f)
      • S(f);SBLOCK::S(H)
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