Problem Display
PID: 23456 (6Q1/2p2R1B/2P3R1/4N3/P2k4/8/3P4/4K3 w - - 0 1)

Valois, Paul Stedman

3rd Prize, McWilliam Ty., 1963

6Q1/2p2R1B/2P3R1/4N3/P2k4/8/3P4/4K3

#2

9 + 2


5454 Near Snap 2009

SOLUTION


  • SOUND
  • Tries
    • 1.Sd7?
      • 1...Kd3
        • 2.Rg4#
      • 1...Ke4
        • 2.Rd6#
      • 1...Kd5
        • 2.Rf4#
      • 1...Kc4!
    • 1.Rf4+?
      • 1...Kc5
        • 2.Sd7#
      • 1...Kxe5!
    • 1.Rf5?
      • threat
        • 2.Qc4#
      • 1...Ke4
        • 2.Rg4#
      • 1...Kc5!
    • 1.Re7?
      • threat
        • 2.Qc4#
      • 1...Ke4
        • 2.Rg4#
      • 1...Kc5!
  • Keys
    • 1.Sd3!
      • 1...Kxd3
        • 2.Rg4#
      • 1...Kc4
        • 2.Rd7#
      • 1...Ke4
        • 2.Rd6#
      • 1...Kd5
        • 2.Rf4#

Anticipated by 187975(1910), 79724(1922), 169818(1945), 77081(1948)

This anticipates 93816(1968), 243965(1986), 7474(1990), 7367(1999), 96631(2005)

FEATURES


  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 0
    • ADDED MATES = 4
    • REMOVED MATES = 0
  • Sets
  • Tries
    • Try
      • S(D);
      • Vars
        • K(a);P-FLIGHT::B(H)+R(F)
        • K(a);P-FLIGHT::QAB(I)+R(G)
      • Refutation
        • K(a);P-FLIGHT
    • Try
      • R(G);CHECK
      • Vars
        • K(a);S_FLIGHT::S(D)
      • Refutation
        • K(a);S_FLIGHT,XS(D)
    • Try
      • R(G);
      • Threat
        • QAR1(I)
      • Vars
        • K(a);P-FLIGHT::R(F)
      • Refutation
        • K(a);S_FLIGHT
    • Try
      • R(G);
      • Threat
        • QAR1(I)
      • Vars
        • K(a);P-FLIGHT::B(H)+R(F),DCHECK
      • Refutation
        • K(a);S_FLIGHT
  • Actual
    • S(D);
    • Vars
      • K(a);P-FLIGHT,XS(D)::B(H)+R(F)
      • K(a);P-FLIGHT::QAB(I)+R(G)
      • K(a);P-FLIGHT::B(H)+R(F)


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).