MESON Chess Problem Database

Problem Display
PID: 274609 (rb6/8/k1N4Q/4pq1b/8/1R1N4/1p3P2/1K3B2 w - - 0 1)

Ohquist, Johannes

Die Schwalbe, 1933

rb6/8/k1N4Q/4pq1b/8/1R1N4/1p3P2/1K3B2

#2

7 + 7

SOLUTION

  • SOUND
  • Sets
    • 1...Qxd3+
      • 2.Bxd3#
    • 1...Qh3
      • 2.Sc5#
    • 1...Qg4
      • 2.Sc5#
    • 1...Qe6
      • 2.Sc5#
    • 1...Qd7
      • 2.Sc5#
    • 1...Qc8
      • 2.Sc5#
    • 1...Qxf2
      • 2.Sc5#
    • 1...Qf3
      • 2.Sc5#
    • 1...Qf4
      • 2.Sc5#
    • 1...Qg5
      • 2.Sc5#
    • 1...Qf6
      • 2.Sc5#
    • 1...Qf7
      • 2.Sc5#
    • 1...Qf8
      • 2.Sc5#
    • 1...e4
      • 2.Sc5#
  • Tries
    • 1.Kxb2?
      • threat
        • 2.Sc5#
      • 1...Qxd3
        • 2.Bxd3#
      • 1...Qxf2+!
    • 1.Sxb8+?
      • 1...Ka7
        • 2.Qe3#
        • 2.Qa6#
        • 2.Qb6#
      • 1...Ka5!
    • 1.Qd2?
      • threat
        • 2.Qa5#
      • 1...Qxd3+
        • 2.Bxd3#
        • 2.Qxd3#
      • 1...e4
        • 2.Sc5#
      • 1...Bc7!
    • 1.Qe6?
      • threat
        • 2.Qc4#
      • 1...Qxd3+
        • 2.Bxd3#
      • 1...Qxe6
        • 2.Sc5#
      • 1...Qe4
        • 2.Qc8#
      • 1...Qg4
        • 2.Sc5#
      • 1...Qf4
        • 2.Sc5#
        • 2.Qc8#
      • 1...Qf7
        • 2.Sc5#
      • 1...e4
        • 2.Sc5#
      • 1...Bf7!
  • Keys
    • 1.Qf8!
      • threat
        • 2.Qa3#
      • 1...Qxd3+
        • 2.Bxd3#
      • 1...Qxf8
        • 2.Sc5#
      • 1...Qe4
        • 2.Qc8#
      • 1...Qg4
        • 2.Sc5#
      • 1...Qf4
        • 2.Sc5#
        • 2.Qc8#
      • 1...Bd6
        • 2.Qxa8#
      • 1...Bc7
        • 2.Qxa8#
      • 1...e4
        • 2.Sc5#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 0
    • ADDED MATES = 3
    • REMOVED MATES = 10
  • Sets
    • Q(c);CHECK,OGATE,P_SPINQ(c),XS(E)::B(B),XQ(c)
    • Q(c);N_PINS(E)::B(B)+S(E),DCHECK
    • Q(c);N_PINS(E),XP(C)::B(B)+S(E),DCHECK
    • P(b);N_PINS(E)::B(B)+S(E),DCHECK
  • Tries
    • Try
      • K(A);N_SPINS(E),P-FLIGHT,XP(a)
      • Threat
        • B(B)+S(E),DCHECK
      • Vars
        • Q(c);OGATE,P_SPINQ(c),XS(E)::B(B),XQ(c)
      • Refutation
        • Q(c);CHECK,XP(C)
    • Try
      • S(F);CHECK,XB(g)
      • Refutation
        • K(e);P-FLIGHT
    • Try
      • Q(G);
      • Threat
        • QAR1(G)
      • Vars
        • P(b);N_PINS(E)::B(B)+S(E),DCHECK
      • Refutation
        • B(g);
    • Try
      • Q(G);
      • Threat
        • QAB(G)
      • Vars
        • Q(c);CHECK,OGATE,P_SPINQ(c),XS(E)::B(B),XQ(c)
        • Q(c);N_PINS(E),XQ(G)::B(B)+S(E),DCHECK
        • Q(c);N_GUARD::QAB(G)
        • Q(c);N_PINS(E)::B(B)+S(E),DCHECK
        • P(b);N_PINS(E)::B(B)+S(E),DCHECK
      • Refutation
        • B(d);
  • Actual
    • Q(G);
    • Threat
      • QAR(G)
    • Vars
      • Q(c);CHECK,OGATE,P_SPINQ(c),XS(E)::B(B),XQ(c)
      • Q(c);N_PINS(E),XQ(G)::B(B)+S(E),DCHECK
      • Q(c);N_GUARD::QAB(G)
      • Q(c);N_PINS(E)::B(B)+S(E),DCHECK
      • B(g);OGATE::QAR2(G),XR(f)
      • P(b);N_PINS(E)::B(B)+S(E),DCHECK
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