MESON Chess Problem Database

Problem Display
PID: 211133 (B7/p1K5/p3p1N1/P1Rq4/3Pk1P1/3R4/2P5/8 w - - 0 1)

Williams, Philip Hamilton

The Observer, 1921

(First published on Sun Oct 23 1921)

B7/p1K5/p3p1N1/P1Rq4/3Pk1P1/3R4/2P5/8

#2

9 + 5

15239 Valois Notebooks 2020
5454 Near Snap 2022

SOLUTION

  • SOUND
  • Sets
    • 1...Qc6+
      • 2.Bxc6#
    • 1...Qb7+
      • 2.Bxb7#
    • 1...Qxa8
      • 2.Re5#
    • 1...e5
      • 2.Bxd5#
  • Tries
    • 1.Kb8?
      • 1...Qb7+
        • 2.Bxb7#
      • 1...Qc6
        • 2.Bxc6#
        • 2.Re5#
      • 1...e5
        • 2.Bxd5#
      • 1...Qxa8+!
    • 1.Kc8?
      • 1...Qc6+
        • 2.Bxc6#
      • 1...Qb7+
        • 2.Bxb7#
      • 1...e5
        • 2.Bxd5#
      • 1...Qxa8+!
    • 1.Bc6?
      • 1...e5
        • 2.Bxd5#
      • 1...Qxc6+!
    • 1.Bb7?
      • 1...Qc6+
        • 2.Bxc6#
      • 1...e5
        • 2.Bxd5#
      • 1...Qxb7+!
    • 1.Rb5?
      • 1...Qc6+
        • 2.Bxc6#
      • 1...Qb7+
        • 2.Bxb7#
      • 1...Qxa8
        • 2.Re5#
      • 1...e5
        • 2.Bxd5#
      • 1...axb5!
    • 1.Rxd5?
      • threat
        • 2.Rb5#
        • 2.Rc5#
        • 2.Re5#
        • 2.Rf5#
        • 2.Rg5#
        • 2.Rh5#
        • 2.Rd6#
        • 2.Rd7#
        • 2.Rd8#
      • 1...e5
        • 2.Rb5#
        • 2.Rc5#
        • 2.Rxe5#
        • 2.Rd6#
        • 2.Rd7#
        • 2.Rd8#
      • 1...exd5!
  • Keys
    • 1.Rc4!
      • 1...Qc6+
        • 2.Bxc6#
      • 1...Qb7+
        • 2.Bxb7#
      • 1...Qxa8
        • 2.d5#
      • 1...e5
        • 2.dxe5#

This anticipates 233554(1979)

FEATURES

  • Static
    • TYPE = MUTATE
    • CHANGED MATES = 2
    • ADDED MATES = 0
    • REMOVED MATES = 0
  • Sets
    • Q(b);CHECK,OGATEB::B(I),XQ(b)
    • Q(b);N_SPINQ(b),OGATE,XB(I)::R1(F)
    • P(d);N_GUARD::B(I),XQ(b)
  • Tries
    • Try
      • K(H);S_FLIGHT
      • Vars
        • Q(b);CHECK,OGATEB::B(I),XQ(b)
        • P(d);N_GUARD::B(I),XQ(b)
      • Refutation
        • Q(b);CHECK,N_SPINQ(b),XB(I)
    • Try
      • K(H);P-FLIGHT
      • Vars
        • Q(b);CHECK,OGATEB::B(I),XQ(b)
        • P(d);N_GUARD::B(I),XQ(b)
      • Refutation
        • Q(b);CHECK,N_SPINQ(b),XB(I)
    • Try
      • B(I);
      • Vars
        • P(d);N_GUARD::B(I),XQ(b)
      • Refutation
        • Q(b);CHECK,N_SPINQ(b),XB(I)
    • Try
      • B(I);
      • Vars
        • Q(b);CHECK,OGATEB::B(I),XQ(b)
        • P(d);N_GUARD::B(I),XQ(b)
      • Refutation
        • Q(b);CHECK,N_SPINQ(b),XB(I)
    • Try
      • R(F);
      • Vars
        • Q(b);CHECK,OGATEB::B(I),XQ(b)
        • Q(b);N_SPINQ(b),OGATE,XB(I)::R1(F)
        • P(d);N_GUARD::B(I),XQ(b)
      • Refutation
        • P(c);XR(F)
    • Try
      • R(F);XQ(b)
      • Threat
        • DUALS(9)
      • Refutation
        • P(d);P_SPINP(d),XR(F)
  • Actual
    • R(F);
    • Vars
      • Q(b);CHECK,OGATEB::B(I),XQ(b)
      • Q(b);N_SPINQ(b),OGATE,XB(I)::R(F)+P(C)
      • P(d);OGATE::R(F)+P(C),XP(d)
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