Problem Display
PID: 16419 (8/6p1/3P2K1/2p5/2kq2R1/2N5/2Q2N2/8 w - - 0 1)

Wenman, Francis Percival (aka Percy Wenman)

Fifty Two-Move Problems, 1940

8/6p1/3P2K1/2p5/2kq2R1/2N5/2Q2N2/8

#2

6 + 4


5454 Near Snap 2007

SOLUTION


  • SOUND
  • Sets
    • 1...Qe4+
      • 2.Rxe4#
    • 1...Qf4
      • 2.Rxf4#
  • Tries
    • 1.Sfd1?
      • 1...Qe4+
        • 2.Rxe4#
      • 1...Kb4
        • 2.Qa4#
      • 1...Qf4
        • 2.Rxf4#
      • 1...Qxg4+!
    • 1.Sd3?
      • 1...Qe4+
        • 2.Rxe4#
      • 1...Qf4
        • 2.Rxf4#
      • 1...Qxg4+!
    • 1.Qb2?
      • 1...Qe4+
        • 2.Rxe4#
      • 1...Qf4
        • 2.Rxf4#
      • 1...Qxg4+!
  • Keys
    • 1.Sfe4!
      • 1...Qf6+
        • 2.Sxf6#
      • 1...Qxe4+
        • 2.Rxe4#
      • 1...Qxd6+
        • 2.Sxd6#
      • 1...Kb4
        • 2.Qa4#
      • 1...Qxc3
        • 2.Sxc3#
      • 1...Qg1
        • 2.Sd2#
      • 1...Qf2
        • 2.Sd2#
        • 2.Sxf2#
      • 1...Qe3
        • 2.Sd2#
      • 1...Qe5
        • 2.Sd2#
      • 1...Qd1
        • 2.Sd2#
      • 1...Qd2
        • 2.Sxd2#
      • 1...Qd3
        • 2.Qa4#
      • 1...Qd5
        • 2.Sd2#

Anticipated by 21594(1920), 203496(1924)

FEATURES


  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 0
    • ADDED MATES = 11
    • REMOVED MATES = 1
  • Sets
    • Q(b);CHECK,OGATEB::R(D),XQ(b)
    • Q(b);OGATEB::R(D),XQ(b)
  • Tries
    • Try
      • S(B);
      • Vars
        • Q(b);CHECK,OGATEB::R(D),XQ(b)
        • K(a);P-FLIGHT::QAR1(A)
        • Q(b);OGATEB::R(D),XQ(b)
      • Refutation
        • Q(b);CHECK,N_SPINQ(b),XR(D)
    • Try
      • S(B);
      • Vars
        • Q(b);CHECK,OGATEB::R(D),XQ(b)
        • Q(b);OGATEB::R(D),XQ(b)
      • Refutation
        • Q(b);CHECK,N_SPINQ(b),XR(D)
    • Try
      • Q(A);
      • Vars
        • Q(b);CHECK,OGATEB::R(D),XQ(b)
        • Q(b);OGATEB::R(D),XQ(b)
      • Refutation
        • Q(b);CHECK,N_SPINQ(b),XR(D)
  • Actual
    • S(B);N_PINQ(b)
    • Vars
      • Q(b);CHECK::R(D)+S(B),XQ(b)
      • Q(b);CHECK,OGATE,P_SPINQ(b),XS(B)::R(D),XQ(b)
      • Q(b);CHECK,XP(E)::R(D)+S(B),DCHECK,XQ(b)
      • K(a);P-FLIGHT::QAR1(A)
      • Q(b);P_SPINQ(b),XS(C)::R(D)+S(B),XQ(b)
      • Q(b);P_PINR(D)::R(D)+S(B),DCHECK
      • Q(b);::R(D)+S(B),DCHECK
      • Q(b);::R(D)+S(B),DCHECK,XQ(b)
      • Q(b);P_PINS(B),SBLOCK::QAR2(A)


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).