Problem Display
PID: 247669 (2K4B/3B4/8/2kp4/8/8/8/7Q w - - 0 1)

Birnov, Zinovy Markovich

Stalingradskaya Pravda, 1955

2K4B/3B4/8/2kp4/8/8/8/7Q

#2

4 + 2


9939 64 Shakhmatnoe obozrenie 2021
5454 Near Snap 2021
3713 Snap 2021

SOLUTION


  • SOUND
  • Tries
    • 1.Qb1?
      • 1...Kc4
        • 2.Qb5#
      • 1...Kd6
        • 2.Qb4#
      • 1...d4!
    • 1.Qc1+?
      • 1...Kb4
        • 2.Qc3#
      • 1...Kd6
        • 2.Qa3#
      • 1...Kb6!
    • 1.Qh4?
      • 1...Kd6
        • 2.Qb4#
      • 1...d4
        • 2.Qxd4#
      • 1...Kb6!
  • Keys
    • 1.Qa1!
      • 1...Kb4
        • 2.Qc3#
      • 1...Kc4
        • 2.Qc3#
      • 1...Kb6
        • 2.Bd4#
      • 1...Kd6
        • 2.Qa3#
      • 1...d4
        • 2.Qxd4#

Anticipated by 178320(1923)

This anticipates 80929(1964)

FEATURES


  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 0
    • ADDED MATES = 5
    • REMOVED MATES = 0
  • Sets
  • Tries
    • Try
      • Q(A);
      • Vars
        • K(a);P-FLIGHT::QAB1(A)
        • K(a);S_FLIGHT::QAB(A)
      • Refutation
        • P(b);
    • Try
      • Q(A);CHECK
      • Vars
        • K(a);S_FLIGHT::QAB1(A)
        • K(a);S_FLIGHT::QAB(A)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • Q(A);
      • Vars
        • K(a);S_FLIGHT::QAB(A)
        • P(b);::QAB1(A),XP(b)
      • Refutation
        • K(a);S_FLIGHT
  • Actual
    • Q(A);
    • Vars
      • K(a);S_FLIGHT::QAB1(A)
      • K(a);P-FLIGHT::QAR1(A)
      • K(a);S_FLIGHT::B(D)
      • K(a);S_FLIGHT::QAB(A)
      • P(b);::QAB1(A),XP(b)


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).