Problem Display
PID: 88777 (8/8/2Q5/8/8/3k1K2/3pNn2/3n4 w - - 0 1)

Lincoln, Robert A

The Problemist, 1993

8/8/2Q5/8/8/3k1K2/3pNn2/3n4

#2

3 + 4


5454 Near Snap 2009
6490 yacpdb 2009

SOLUTION


  • SOUND
  • Sets
    • 1...Sb2
      • 2.Qc3#
    • 1...Sc3
      • 2.Qxc3#
    • 1...Se3
      • 2.Qc3#
    • 1...Sh1
      • 2.Qe4#
    • 1...Sh3
      • 2.Qe4#
    • 1...Se4
      • 2.Qxe4#
    • 1...Sg4
      • 2.Qe4#
  • Tries
    • 1.Qc5?
      • threat
        • 2.Sf4#
      • 1...Sc3
        • 2.Qxc3#
      • 1...Sh3!
    • 1.Qg6+?
      • 1...Se4
        • 2.Qxe4#
      • 1...Kc4!
  • Keys
    • 1.Qa4!
      • 1...Sb2
        • 2.Qb3#
      • 1...Sc3
        • 2.Sf4#
      • 1...Se3
        • 2.Qb3#
      • 1...Sh1
        • 2.Qe4#
      • 1...Sh3
        • 2.Qe4#
      • 1...Se4
        • 2.Qxe4#
      • 1...Sg4
        • 2.Qe4#

Anticipated by 51849(1920), 23429(1924), 16843(1943), 96731(1944), 18147(1953), 108913(1970)

This anticipates 16255(2000)

FEATURES


  • Static
    • TYPE = MUTATE
    • CHANGED MATES = 3
    • ADDED MATES = 0
    • REMOVED MATES = 0
  • Sets
    • S(a);N_GUARD::QAR1(C)
    • S(a);N_GUARD::QAR1(C),XS(a)
    • S(c);N_GUARD::QAB1(C)
    • S(c);N_GUARD::QAB1(C),XS(c)
  • Tries
    • Try
      • Q(C);
      • Threat
        • S(A)
      • Vars
        • S(a);N_GUARD::QAR1(C),XS(a)
      • Refutation
        • S(c);
    • Try
      • Q(C);CHECK
      • Vars
        • S(c);N_GUARD,P_SPINS(c)::QAB1(C),XS(c)
      • Refutation
        • K(d);S_FLIGHT
  • Actual
    • Q(C);
    • Vars
      • S(a);N_GUARD::QAR2(C)
      • S(a);SBLOCK::S(A)
      • S(c);N_GUARD::QAB1(C)
      • S(c);N_GUARD::QAB1(C),XS(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).