MESON Chess Problem Database

Problem Display
PID: 150698 (8/B7/8/kp1K4/N7/8/Q7/3B4 w - - 0 1)

Ahlheim, Karl-Heinz

Die Schwalbe, 1982

8/B7/8/kp1K4/N7/8/Q7/3B4

#2

5 + 2

15148 Sadier Collection 2014
5454 Near Snap 2021

SOLUTION

  • SOUND
  • Sets
    • 1...Ka6
      • 2.Sc5#
    • 1...bxa4
      • 2.Qxa4#
    • 1...b4
      • 2.Sc3#
  • Tries
    • 1.Kd4?
      • 1...Ka6
        • 2.Sc5#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Kb4!
    • 1.Ke4?
      • 1...Ka6
        • 2.Sc5#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Kb4!
    • 1.Kc5?
      • threat
        • 2.Sb2#
        • 2.Sc3#
        • 2.Sb6#
      • 1...bxa4
        • 2.Qxa4#
      • 1...Ka6!
    • 1.Ke5?
      • 1...Ka6
        • 2.Sc5#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Kb4!
    • 1.Kc6?
      • 1...Ka6
        • 2.Sb2#
        • 2.Sc3#
        • 2.Sc5#
        • 2.Sb6#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sb2#
        • 2.Sc3#
        • 2.Sc5#
        • 2.Sb6#
      • 1...Kb4!
    • 1.Kd6?
      • 1...Ka6
        • 2.Sc5#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Kb4!
    • 1.Ke6?
      • 1...Ka6
        • 2.Sc5#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Kb4!
    • 1.Bc2?
      • 1...Ka6
        • 2.Sc5#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Kb4!
    • 1.Be2?
      • 1...Ka6
        • 2.Sc5#
      • 1...bxa4
        • 2.Qd2#
      • 1...b4
        • 2.Sb2#
        • 2.Sc3#
        • 2.Sc5#
        • 2.Sb6#
        • 2.Bb6#
      • 1...Kb4!
    • 1.Bb3?
      • 1...Ka6
        • 2.Sc5#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Kb4!
    • 1.Bf2?
      • 1...Kb4
        • 2.Be1#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Ka6!
    • 1.Be3?
      • 1...Kb4
        • 2.Bd2#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Ka6!
    • 1.Bd4?
      • 1...Kb4
        • 2.Bc3#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Ka6!
    • 1.Bc5?
      • threat
        • 2.Sb2#
        • 2.Sc3#
        • 2.Sb6#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#
      • 1...Ka6!
    • 1.Bb6+?
      • 1...Kb4
        • 2.Qb3#
        • 2.Qb2#
      • 1...Ka6!
    • 1.Qf2?
      • 1...Ka6
        • 2.Qb6#
      • 1...bxa4
        • 2.Qb6#
      • 1...b4
        • 2.Qb6#
      • 1...Kb4!
    • 1.Qa3?
      • threat
        • 2.Sb2#
        • 2.Sc3#
        • 2.Sc5#
        • 2.Sb6#
      • 1...Ka6
        • 2.Sc5#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4!
  • Keys
    • 1.Qa1!
      • 1...Kb4
        • 2.Qc3#
      • 1...Ka6
        • 2.Sc5#
      • 1...bxa4
        • 2.Qxa4#
      • 1...b4
        • 2.Sc3#

Anticipated by 21309(1918), 77239(1927), 102513(1964), 12404(1978)

This anticipates 79321(1988), 203054(1990), 245207(2000)

FEATURES

  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 0
    • ADDED MATES = 1
    • REMOVED MATES = 0
  • Sets
    • K(a);P-FLIGHT::QAR(B)+S(C),DCHECK
    • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
    • P(b);SBLOCK::QAR(B)+S(C)
  • Tries
    • Try
      • K(D);P-FLIGHT
      • Vars
        • K(a);P-FLIGHT::QAR(B)+S(C),DCHECK
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);SBLOCK::QAR(B)+S(C)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • K(D);S_FLIGHT
      • Vars
        • K(a);P-FLIGHT::QAR(B)+S(C),DCHECK
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);SBLOCK::QAR(B)+S(C)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • K(D);P-FLIGHT
      • Threat
        • DUALS(3)
      • Vars
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
      • Refutation
        • K(a);P-FLIGHT
    • Try
      • K(D);P-FLIGHT
      • Vars
        • K(a);P-FLIGHT::QAR(B)+S(C),DCHECK
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);SBLOCK::QAR(B)+S(C)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • K(D);S_FLIGHT
      • Vars
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • K(D);P-FLIGHT
      • Vars
        • K(a);P-FLIGHT::QAR(B)+S(C),DCHECK
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);SBLOCK::QAR(B)+S(C)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • K(D);S_FLIGHT
      • Vars
        • K(a);P-FLIGHT::QAR(B)+S(C),DCHECK
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);SBLOCK::QAR(B)+S(C)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • B(A);
      • Vars
        • K(a);P-FLIGHT::QAR(B)+S(C),DCHECK
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);SBLOCK::QAR(B)+S(C)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • B(A);
      • Vars
        • K(a);P-FLIGHT,P_SPINP(b)::QAR(B)+S(C),DCHECK
        • P(b);N_GUARD,P_SPINP(b),SBLOCK,XS(C)::QAB(B)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • B(A);
      • Vars
        • K(a);P-FLIGHT::QAR(B)+S(C),DCHECK
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);SBLOCK::QAR(B)+S(C)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • B(E);
      • Vars
        • K(a);S_FLIGHT::B(E)
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);SBLOCK::QAR(B)+S(C)
      • Refutation
        • K(a);P-FLIGHT
    • Try
      • B(E);
      • Vars
        • K(a);S_FLIGHT::B(E)
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);SBLOCK::QAR(B)+S(C)
      • Refutation
        • K(a);P-FLIGHT
    • Try
      • B(E);
      • Vars
        • K(a);S_FLIGHT::B(E)
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);SBLOCK::QAR(B)+S(C)
      • Refutation
        • K(a);P-FLIGHT
    • Try
      • B(E);
      • Threat
        • DUALS(3)
      • Vars
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
        • P(b);::QAR(B)+S(C)
      • Refutation
        • K(a);P-FLIGHT
    • Try
      • B(E);CHECK
      • Refutation
        • K(a);P-FLIGHT
    • Try
      • Q(B);
      • Vars
        • K(a);P-FLIGHT::QAR1(B)
        • P(b);XS(C)::QAB1(B)
        • P(b);::QAB1(B)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • Q(B);
      • Threat
        • DUALS(4)
      • Vars
        • K(a);P-FLIGHT::QAR(B)+S(C),DCHECK
        • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
      • Refutation
        • P(b);
  • Actual
    • Q(B);
    • Vars
      • K(a);S_FLIGHT::QAB1(B)
      • K(a);P-FLIGHT::QAR(B)+S(C),DCHECK
      • P(b);OGATE,P_SPINP(b),XS(C)::QAR1(B),XP(b)
      • P(b);SBLOCK::QAR(B)+S(C)
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