MESON Chess Problem Database

Problem Display
PID: 153953 (8/8/n7/N5Q1/pk6/7R/8/4K3 w - - 0 1)

Harley, Brian

The Observer, 1952

(First published on Sun Sep 7 1952)

8/8/n7/N5Q1/pk6/7R/8/4K3

#2

4 + 3

15290 Harley Scrapbook 2015
5454 Near Snap 2019
15239 Valois Notebooks 2020

SOLUTION

  • SOUND
  • Tries
    • 1.Rh4+?
      • 1...Kc3
        • 2.Qd2#
      • 1...Ka3!
  • Keys
    • 1.Rc3!
      • 1...Kxc3
        • 2.Qd2#
      • 1...Sc5
        • 2.Qxc5#
      • 1...a3
        • 2.Rc4#
      • 1...Sc7
        • 2.Qc5#
      • 1...Sb8
        • 2.Qc5#

Anticipated by 1962(1859), 121007(1899), 205348(1949)

FEATURES

  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 0
    • ADDED MATES = 5
    • REMOVED MATES = 0
  • Sets
  • Tries
    • Try
      • R(B);CHECK
      • Vars
        • K(b);S_FLIGHT::QAB1(D)
      • Refutation
        • K(b);S_FLIGHT
  • Actual
    • R(B);
    • Vars
      • K(b);OGATEB,S_FLIGHT,XR(B)::QAB1(D)
      • S(c);N_GUARD::QAB1(D),XS(c)
      • P(a);SBLOCK::R1(B)
      • S(c);N_GUARD::QAB1(D)
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