MESON Chess Problem Database

Problem Display
PID: 58764 (2N3bK/3pprpp/R6q/n1pkNB2/2p1p3/8/QB6/8 w - - 0 1)

O'Keefe, John James

2nd HM., Brisbane Courier, 1920-1921

2N3bK/3pprpp/R6q/n1pkNB2/2p1p3/8/QB6/8

#2

7 + 12

SOLUTION

  • SOUND
  • Sets
    • 1...Rxf5
      • 2.Sxe7#
    • 1...Rf6
      • 2.Sxe7#
    • 1...Rf8
      • 2.Sxe7#
    • 1...Sc6
      • 2.Qxc4#
    • 1...Sb7
      • 2.Qxc4#
    • 1...d6
      • 2.Sb6#
    • 1...e6
      • 2.Rd6#
  • Tries
    • 1.Rd6+?
      • 1...exd6
        • 2.Sb6#
      • 1...Qxd6!
  • Keys
    • 1.Qa4!
      • 1...Qxa6
        • 2.Qd1#
      • 1...Rxf5
        • 2.Sxe7#
      • 1...c3
        • 2.Qxe4#
      • 1...Qc1
        • 2.Qxd7#
      • 1...Qd2
        • 2.Qxd7#
      • 1...Qe3
        • 2.Qxd7#
      • 1...Qf4
        • 2.Qxd7#
      • 1...Qg5
        • 2.Qxd7#
      • 1...Qh1
        • 2.Qxd7#
      • 1...Qh2
        • 2.Qxd7#
      • 1...Qh3
        • 2.Qxd7#
      • 1...Qh4
        • 2.Qd1#
        • 2.Qxd7#
      • 1...Qh5
        • 2.Qxd7#
      • 1...Qb6
        • 2.Qd1#
      • 1...Qc6
        • 2.Qd1#
      • 1...Qd6
        • 2.Qd1#
      • 1...Qe6
        • 2.Qd1#
      • 1...Qf6
        • 2.Qd1#
      • 1...Qg6
        • 2.Qd1#
      • 1...Rf6
        • 2.Sxe7#
      • 1...Rf8
        • 2.Sxe7#
      • 1...Sb3
        • 2.Qxc4#
      • 1...Sc6
        • 2.Qxc4#
      • 1...Sb7
        • 2.Qxc4#
      • 1...e3
        • 2.Qd1#
      • 1...d6
        • 2.Sb6#
      • 1...e6
        • 2.Rd6#
      • 1...g5
        • 2.Qd1#
      • 1...g6
        • 2.Qxd7#

FEATURES

  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 0
    • ADDED MATES = 21
    • REMOVED MATES = 0
  • Sets
    • R(i);N_GUARD,XB(D)::S(F),XP(h)
    • R(i);N_GUARD::S(F),XP(h)
    • S(c);N_GUARD::QAB1(A),XP(a)
    • P(g);SBLOCK,S_CUTQ(f)::S(F)
    • P(h);N_GUARD,S_CUTQ(f)::R1(E)
  • Tries
    • Try
      • R(E);CHECK
      • Vars
        • P(h);SBLOCK,XR(E)::S(F)
      • Refutation
        • Q(f);XR(E)
  • Actual
    • Q(A);N_PINP(a)
    • Vars
      • Q(f);N_GUARD,XR(E)::QAR(A)
      • R(i);N_GUARD,XB(D)::S(F),XP(h)
      • P(a);OGATE::QAB1(A),XP(b)
      • Q(f);N_GUARD::QAR2(A),XP(g)
      • Q(f);N_GUARD::QAR(A)
      • R(i);N_GUARD::S(F),XP(h)
      • S(c);N_GUARD::QAB1(A),XP(a)
      • P(b);S_CUTQ(f)::QAR(A)
      • P(g);SBLOCK,S_CUTQ(f)::S(F)
      • P(h);N_GUARD,S_CUTQ(f)::R1(E)
      • P(j);S_CUTQ(f)::QAR(A)
      • P(j);S_CUTQ(f)::QAR2(A),XP(g)
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