MESON Chess Problem Database

Problem Display
PID: 79979 (8/8/8/p2N4/6Q1/rk6/8/nK6 w - - 0 1)

Lincoln, Robert A

The Problemist Supplement, 2008

8/8/8/p2N4/6Q1/rk6/8/nK6

#2

3 + 4

SOLUTION

  • SOUND
  • Sets
    • 1...a4
      • 2.Qb4#
  • Tries
    • 1.Qd1+?
      • 1...Sc2
        • 2.Qxc2#
      • 1...Kc4!
    • 1.Qc8?
      • 1...Ka4
        • 2.Qc4#
      • 1...Ra4
        • 2.Qc3#
      • 1...Sc2
        • 2.Qxc2#
      • 1...a4
        • 2.Qc3#
      • 1...Ra2!
    • 1.Qe4?
      • 1...Ra4
        • 2.Qd3#
      • 1...Sc2
        • 2.Qxc2#
      • 1...a4
        • 2.Qd3#
        • 2.Qb4#
      • 1...Ra2!
  • Keys
    • 1.Qe2!
      • threat
        • 2.Qb5#
      • 1...Ka4
        • 2.Qc4#
      • 1...Ra2
        • 2.Qxa2#
      • 1...Ra4
        • 2.Qd3#
      • 1...Sc2
        • 2.Qxc2#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 0
    • ADDED MATES = 4
    • REMOVED MATES = 1
  • Sets
    • P(d);N_GUARD::QAR1(B)
  • Tries
    • Try
      • Q(B);CHECK
      • Vars
        • S(a);N_GUARD,P_SPINS(a)::QAB1(B),XS(a)
      • Refutation
        • K(c);S_FLIGHT
    • Try
      • Q(B);
      • Vars
        • K(c);S_FLIGHT::QAR2(B)
        • R(b);SBLOCK::QAR1(B)
        • S(a);N_GUARD::QAB1(B),XS(a)
        • P(d);SBLOCK::QAR1(B)
      • Refutation
        • R(b);
    • Try
      • Q(B);
      • Vars
        • R(b);SBLOCK::QAR2(B)
        • S(a);N_GUARD::QAB1(B),XS(a)
      • Refutation
        • R(b);
  • Actual
    • Q(B);
    • Threat
      • QAR2(B)
    • Vars
      • K(c);S_FLIGHT::QAR2(B)
      • R(b);N_GUARD::QAB1(B),XR(b)
      • R(b);SBLOCK::QAR2(B)
      • S(a);N_GUARD::QAB1(B),XS(a)
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