MESON Chess Problem Database

Problem Display
PID: 1099 (8/8/1pQ4B/1p2N3/4Nq2/4k3/1K1R3n/1n4b1 w - - 0 1)

Callander, Charles

The Westminster Papers, 1873

8/8/1pQ4B/1p2N3/4Nq2/4k3/1K1R3n/1n4b1

#2

6 + 7

1693 English Chess Problems 1876
3360 Simple Two-move Themes 1924
56 The Problemist 2006
3713 Snap 2015

SOLUTION

  • SOUND
  • Sets
    • 1...Qg5
      • 2.Bxg5#
    • 1...Sf3
      • 2.Sg4#
  • Tries
    • 1.Re2+?
      • 1...Kd4
        • 2.Qd6#
      • 1...Kxe2!
    • 1.Qd5?
      • threat
        • 2.Qd3#
        • 2.Qd4#
      • 1...Sxd2
        • 2.Qd3#
      • 1...Qg5
        • 2.Bxg5#
      • 1...Sf3
        • 2.Sg4#
        • 2.Qd3#
      • 1...Qxh6!
    • 1.Qc2?
      • threat
        • 2.Qd3#
      • 1...Qg5
        • 2.Bxg5#
      • 1...Qxh6!
  • Keys
    • 1.Sg3!
      • 1...Kxd2
        • 2.Qc1#
      • 1...Qxh6
        • 2.Qxh6#
      • 1...Sxd2
        • 2.Qxb6#
      • 1...Qg5
        • 2.Bxg5#
      • 1...Bf2
        • 2.Rd3#
      • 1...Sa3
        • 2.Qc3#
      • 1...Sc3
        • 2.Qxc3#
      • 1...Sf1
        • 2.Sxf1#
      • 1...Sf3
        • 2.Sf1#
      • 1...Sg4
        • 2.Sf1#
      • 1...b4
        • 2.Sc4#

This anticipates 154477(1987)

FEATURES

  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 1
    • ADDED MATES = 9
    • REMOVED MATES = 0
  • Sets
    • Q(e);OGATEB::B(F),XQ(e)
    • S(c);N_GUARD,SBLOCK::S(D)
  • Tries
    • Try
      • R(B);CHECK
      • Vars
        • K(d);N_SPINQ(e),S_FLIGHT::QAR2(E)
      • Refutation
        • K(d);N_SPINQ(e),P-FLIGHT,XR(B)
    • Try
      • Q(E);
      • Threat
        • DUALS(2)
      • Vars
        • S(a);XR(B)::QAR1(E)
        • Q(e);OGATEB::B(F),XQ(e)
      • Refutation
        • Q(e);N_SPINQ(e),XB(F)
    • Try
      • Q(E);
      • Threat
        • QAR1(E)
      • Vars
        • Q(e);OGATEB::B(F),XQ(e)
      • Refutation
        • Q(e);N_SPINQ(e),XB(F)
  • Actual
    • S(C);
    • Vars
      • K(d);OGATEB,S_FLIGHT,XR(B)::QAB1(E)
      • Q(e);N_SPINQ(e),OGATE,XB(F)::QAB(E),XQ(e)
      • S(a);SBLOCK,XR(B)::QAB(E),XP(g)
      • Q(e);OGATEB::B(F),XQ(e)
      • B(b);SBLOCK::R1(B)
      • S(a);N_GUARD::QAR2(E)
      • S(a);N_GUARD::QAR2(E),XS(a)
      • S(c);N_GUARD::S(C),XS(c)
      • S(c);N_GUARD::S(C)
      • P(f);N_GUARD::S(D)
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