MESON Chess Problem Database

Problem Display
PID: 258068 (B7/r7/4p3/8/3Q4/3pK1P1/8/5k2 w - - 0 1)

Nemo, Ottmar (Weiss, Ottmar)

Die Schwalbe, 1931

B7/r7/4p3/8/3Q4/3pK1P1/8/5k2

#2

4 + 4

SOLUTION

  • SOUND
  • Sets
    • 1...Ra1
      • 2.Qxa1#
    • 1...Rd7
      • 2.Qa1#
    • 1...Re7
      • 2.Qa1#
    • 1...Rf7
      • 2.Qa1#
    • 1...Rg7
      • 2.Qa1#
    • 1...Rh7
      • 2.Qa1#
  • Tries
    • 1.Qb2?
      • threat
        • 2.Qc1#
        • 2.Qb1#
        • 2.Qf2#
      • 1...Ke1
        • 2.Qc1#
        • 2.Qb1#
      • 1...Kg1
        • 2.Qf2#
        • 2.Qg2#
      • 1...Rxa8
        • 2.Qf2#
      • 1...Ra1
        • 2.Qxa1#
        • 2.Qf2#
      • 1...Ra2
        • 2.Qc1#
        • 2.Qb1#
      • 1...Rb7
        • 2.Qf2#
      • 1...Rc7
        • 2.Qf2#
      • 1...Rf7
        • 2.Qa1#
        • 2.Qc1#
        • 2.Qb1#
      • 1...d2!
    • 1.Qf6+?
      • 1...Kg1
        • 2.Qf2#
      • 1...Ke1!
    • 1.Qxd3+?
      • 1...Ke1
        • 2.Qb1#
        • 2.Qe2#
      • 1...Kg1!
    • 1.Qe4?
      • threat
        • 2.Qh1#
      • 1...Ke1
        • 2.Qh1#
      • 1...Kg1
        • 2.Qh1#
        • 2.Qg2#
      • 1...Rh7!
    • 1.Qf4+?
      • 1...Kg1
        • 2.Qf2#
      • 1...Ke1!
    • 1.Qh4?
      • threat
        • 2.Qh1#
      • 1...Ke1
        • 2.Qh1#
      • 1...Kg1
        • 2.Qh1#
      • 1...Rh7!
  • Keys
    • 1.Qh8!
      • threat
        • 2.Qh1#
      • 1...Ke1
        • 2.Qh1#
      • 1...Kg1
        • 2.Qh1#
      • 1...Rh7
        • 2.Qa1#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 0
    • ADDED MATES = 2
    • REMOVED MATES = 5
  • Sets
    • R(d);N_GUARD::QAR(C),XR(d)
    • R(d);N_GUARD::QAR(C)
  • Tries
    • Try
      • Q(C);
      • Threat
        • DUALS(3)
      • Vars
        • R(d);XB(D)::QAR1(C)
        • R(d);::QAR1(C)
      • Refutation
        • P(b);
    • Try
      • Q(C);CHECK
      • Vars
        • K(a);P-FLIGHT::QAB1(C)
      • Refutation
        • K(a);P-FLIGHT
    • Try
      • Q(C);CHECK,XP(b)
      • Refutation
        • K(a);P-FLIGHT
    • Try
      • Q(C);
      • Threat
        • QAR2(C)
      • Vars
        • K(a);P-FLIGHT::QAR(C)
      • Refutation
        • R(d);
    • Try
      • Q(C);CHECK
      • Vars
        • K(a);P-FLIGHT::QAB1(C)
      • Refutation
        • K(a);P-FLIGHT
    • Try
      • Q(C);
      • Threat
        • QAR2(C)
      • Vars
        • K(a);P-FLIGHT::QAR(C)
        • K(a);P-FLIGHT::QAR1(C)
      • Refutation
        • R(d);
  • Actual
    • Q(C);
    • Threat
      • QAR2(C)
    • Vars
      • K(a);P-FLIGHT::QAR(C)
      • K(a);P-FLIGHT::QAR1(C)
      • R(d);N_GUARD::QAR(C)
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