Problem Display
PID: 7367 (1B6/Q1R5/1R6/8/2N1k2P/4p3/4P3/3K4 w - - 0 1)

Green, Joshua

StrateGems, 1999

1B6/Q1R5/1R6/8/2N1k2P/4p3/4P3/3K4

#2

8 + 2


5454 Near Snap 2009

SOLUTION


  • SOUND
  • Tries
    • 1.Qa5?
      • threat
        • 2.Qe5#
      • 1...Kd4
        • 2.Qe5#
      • 1...Kf4!
    • 1.Qb7+?
      • 1...Kf4
        • 2.Qf3#
      • 1...Kf5
        • 2.Qf3#
      • 1...Kd4!
    • 1.Qa8+?
      • 1...Kf4
        • 2.Qf3#
      • 1...Kf5
        • 2.Qf3#
      • 1...Kd4!
  • Keys
    • 1.Sxe3!
      • 1...Kxe3
        • 2.Rb4#
      • 1...Kd4
        • 2.Re6#
      • 1...Kf4
        • 2.Re7#
      • 1...Ke5
        • 2.Rc4#

Anticipated by 187975(1910), 79724(1922), 77081(1948), 23456(1963), 93816(1968), 7474(1990)

FEATURES


  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 0
    • ADDED MATES = 4
    • REMOVED MATES = 0
  • Sets
  • Tries
    • Try
      • Q(F);
      • Threat
        • QAR1(F)
      • Vars
        • K(b);P-FLIGHT::QAB1(F)
      • Refutation
        • K(b);P-FLIGHT
    • Try
      • Q(F);CHECK
      • Vars
        • K(b);OGATE,P-FLIGHT::QAR1(F)
        • K(b);OGATE,S_FLIGHT::QAR2(F)
      • Refutation
        • K(b);P-FLIGHT
    • Try
      • Q(F);CHECK
      • Vars
        • K(b);OGATE,P-FLIGHT::QAR1(F)
        • K(b);OGATE,S_FLIGHT::QAR2(F)
      • Refutation
        • K(b);P-FLIGHT
  • Actual
    • S(C);XP(a)
    • Vars
      • K(b);P-FLIGHT,XS(C)::QAB(F)+R(E)
      • K(b);P-FLIGHT::QAB(F)+R(E)
      • K(b);P-FLIGHT::B(H)+R(G)


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).