MESON Chess Problem Database

Problem Display
PID: 213223 (8/5K2/5N1k/8/5P2/4Qn2/8/8 w - - 0 1)

Speckmann, Werner

Land og Folk, 1971

8/5K2/5N1k/8/5P2/4Qn2/8/8

#2

4 + 2

15148 Sadier Collection 2020
5454 Near Snap 2022

SOLUTION

  • SOUND
  • Sets
    • 1...Se1
      • 2.Qh3#
      • 2.f5#
    • 1...Sg1
      • 2.f5#
    • 1...Sd2
      • 2.Qh3#
      • 2.f5#
    • 1...Sh2
      • 2.Qh3#
      • 2.f5#
    • 1...Sd4
      • 2.Qh3#
      • 2.f5#
    • 1...Sh4
      • 2.f5#
    • 1...Se5+
      • 2.fxe5#
    • 1...Sg5+
      • 2.fxg5#
  • Tries
    • 1.Qd2?
      • 1...Se5+
        • 2.fxe5#
      • 1...Sg5+
        • 2.fxg5#
      • 1...Se1
        • 2.Qh2#
        • 2.f5#
      • 1...Sg1
        • 2.f5#
      • 1...Sh2
        • 2.Qxh2#
        • 2.f5#
      • 1...Sd4
        • 2.Qh2#
        • 2.f5#
      • 1...Sh4
        • 2.f5#
      • 1...Sxd2!
    • 1.Qc5?
      • threat
        • 2.Qf8#
        • 2.Qh5#
      • 1...Sg5+
        • 2.Qxg5#
        • 2.fxg5#
      • 1...Se5+!
    • 1.Qe5?
      • threat
        • 2.Qh5#
      • 1...Sg5+
        • 2.Qxg5#
        • 2.fxg5#
      • 1...Sxe5+!
  • Keys
    • 1.Qc1!
      • 1...Se5+
        • 2.fxe5#
      • 1...Sg5+
        • 2.fxg5#
      • 1...Se1
        • 2.f5#
      • 1...Sg1
        • 2.f5#
      • 1...Sd2
        • 2.Qh1#
      • 1...Sh2
        • 2.f5#
      • 1...Sd4
        • 2.Qh1#
        • 2.f5#
      • 1...Sh4
        • 2.f5#

This anticipates 232371(1978)

FEATURES

  • Static
    • TYPE = WAITER
    • CHANGED MATES = 0
    • ADDED MATES = 3
    • REMOVED MATES = 0
  • Sets
    • S(a);N_GUARD::QAB(A)+P(B)
    • S(a);CHECK,OGATE::QAB(A)+P(B),XS(a)
    • S(a);CHECK,OGATE::P(B),XS(a)
  • Tries
    • Try
      • Q(A);
      • Vars
        • S(a);CHECK,OGATE::QAB(A)+P(B),XS(a)
        • S(a);CHECK,OGATE::P(B),XS(a)
        • S(a);N_GUARD::QAB(A)+P(B)
      • Refutation
        • S(a);XQ(A)
    • Try
      • Q(A);
      • Threat
        • DUALS(2)
      • Refutation
        • S(a);CHECK
    • Try
      • Q(A);
      • Threat
        • QAR1(A)
      • Refutation
        • S(a);CHECK,XQ(A)
  • Actual
    • Q(A);
    • Vars
      • S(a);CHECK,OGATE::QAB(A)+P(B),XS(a)
      • S(a);CHECK,OGATE::P(B),XS(a)
      • S(a);N_GUARD::QAB(A)+P(B)
      • S(a);N_GUARD::QAR(A)
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