Problem Display
PID: 196658 (8/7B/Q1K5/3pk3/4N2B/8/8/8 w - - 0 1)

Lebedev, Leonid Arsentevich

Prize, Zvyazda, 1995

8/7B/Q1K5/3pk3/4N2B/8/8/8

#2

5 + 2


5454 Near Snap 2019
133 The Problemist Supplement 2019

SOLUTION


  • SOUND
  • Tries
    • 1.Qf1?
      • threat
        • 2.Qf6#
      • 1...Ke6
        • 2.Qf5#
        • 2.Qf6#
      • 1...Kd4!
    • 1.Qe2?
      • 1...Kd4
        • 2.Bf6#
      • 1...Kf4
        • 2.Bg3#
      • 1...Ke6
        • 2.Sd6#
      • 1...dxe4
        • 2.Qxe4#
      • 1...d4!
    • 1.Qd3?
      • 1...Kf4
        • 2.Qg3#
      • 1...Ke6
        • 2.Qxd5#
      • 1...dxe4
        • 2.Qxe4#
        • 2.Qd6#
      • 1...d4!
    • 1.Qa5?
      • 1...Kd4
        • 2.Qc3#
      • 1...Ke6
        • 2.Qxd5#
      • 1...Kf4!
  • Keys
    • 1.Qa3!
      • 1...Kd4
        • 2.Qc3#
      • 1...Kf4
        • 2.Qg3#
      • 1...Ke6
        • 2.Qe7#
      • 1...dxe4
        • 2.Qd6#
      • 1...d4
        • 2.Qd6#

Anticipated by 86880(1966)

This anticipates 200707(2017)

FEATURES


  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 0
    • ADDED MATES = 5
    • REMOVED MATES = 0
  • Sets
  • Tries
    • Try
      • Q(C);
      • Threat
        • QAB1(C)
      • Refutation
        • K(b);S_FLIGHT
    • Try
      • Q(C);
      • Vars
        • K(b);S_FLIGHT::B(B)
        • K(b);P-FLIGHT::QAR(C)+S(A)
        • P(a);OGATE,P_SPINP(a),XS(A)::QAR1(C),XP(a)
      • Refutation
        • P(a);
    • Try
      • Q(C);
      • Vars
        • K(b);S_FLIGHT::QAB1(C)
        • K(b);P-FLIGHT::QAB1(C),XP(a)
      • Refutation
        • P(a);
    • Try
      • Q(C);P_PINP(a)
      • Vars
        • K(b);N_SPINP(a),S_FLIGHT::QAB1(C)
        • K(b);N_SPINP(a),P-FLIGHT::QAB1(C),XP(a)
      • Refutation
        • K(b);N_SPINP(a),S_FLIGHT
  • Actual
    • Q(C);
    • Vars
      • K(b);S_FLIGHT::QAB1(C)
      • K(b);P-FLIGHT::QAR1(C)
      • P(a);XS(A)::QAB1(C)
      • P(a);::QAB1(C)


Developed and maintained by Brian Stephenson.
Implemented with HTML5, MySQL, Perl (with, inter alia, CGI::Simple, HTML::Template & XML::LibXML) & CSS/Javascript (jQuery, Bootstrap & DataTables).