MESON Chess Problem Database

Problem Display
PID: 21175 (5K2/p1p2N2/2pp1Q1p/qn5p/Rb2k2r/1N6/3R4/4nBB1 w - - 0 1)

O'Keefe, John James

Smith, William James

1st Prize, Good Companions (February), 1917

5K2/p1p2N2/2pp1Q1p/qn5p/Rb2k2r/1N6/3R4/4nBB1

#2

8 + 12

15 British Chess Magazine 1917
3132 The Good Companion Two-Mover 1922
3639 Hastings Solving Ty. 1994-1995
56 The Problemist 2005
5503 ISC 2014

SOLUTION

  • SOUND
  • Sets
    • 1...Sc2
      • 2.Bg2#
    • 1...Sg2
      • 2.Bxg2#
    • 1...Sd3
      • 2.Bg2#
    • 1...Sa3
      • 2.Rd4#
    • 1...Sc3
      • 2.Rd4#
    • 1...Sd4
      • 2.Rxd4#
    • 1...d5+
      • 2.Sc5#
  • Tries
    • 1.Sxd6+?
      • 1...Sxd6
        • 2.Rd4#
      • 1...cxd6!
    • 1.Sxh6?
      • threat
        • 2.Qf5#
      • 1...d5+
        • 2.Sc5#
      • 1...Sd4
        • 2.Rxd4#
      • 1...Sa3
        • 2.Rd4#
      • 1...Sc3
        • 2.Rd4#
      • 1...Rf4!
    • 1.Bg2+?
      • 1...Sf3
        • 2.Bxf3#
        • 2.Qxf3#
      • 1...Sxg2!
    • 1.Bd3+?
      • 1...Kd5
        • 2.Qf5#
      • 1...Sxd3!
    • 1.Re2+?
      • 1...Kd5
        • 2.Qe6#
      • 1...Kd3!
    • 1.Rd5?
      • threat
        • 2.Qf5#
      • 1...Kxd5
        • 2.Qf5#
      • 1...cxd5
        • 2.Sd2#
      • 1...Sd4
        • 2.Rxd4#
      • 1...Rf4!
    • 1.Rxb4+?
      • 1...Sd4
        • 2.Rdxd4#
        • 2.Rbxd4#
      • 1...Qxb4!
  • Keys
    • 1.Rf2!
      • threat
        • 2.Qe6#
      • 1...d5+
        • 2.Qe7#
      • 1...Ke3
        • 2.Rf4#
      • 1...Kd5
        • 2.Qf5#
      • 1...Sd3
        • 2.Qf3#
      • 1...Sf3
        • 2.Qxf3#
      • 1...Sa3
        • 2.Qd4#
      • 1...Sc3
        • 2.Qd4#
      • 1...Sd4
        • 2.Qxd4#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 5
    • ADDED MATES = 3
    • REMOVED MATES = 2
  • Sets
    • S(a);N_GUARD::B(A)
    • S(a);N_GUARD::B(A),XS(a)
    • S(f);N_GUARD::R1(C)
    • S(f);N_GUARD,N_SPINB(b)::R1(C),XS(f)
    • P(i);CHECK,N_GUARD::S(D)
  • Tries
    • Try
      • S(G);CHECK,P_SPINS(G),XP(i)
      • Vars
        • S(f);XS(G)::R1(C)
      • Refutation
        • P(l);XS(G)
    • Try
      • S(G);XP(j)
      • Threat
        • QAB1(F)
      • Vars
        • P(i);CHECK,N_GUARD::S(D)
        • S(f);N_GUARD,N_SPINB(b)::R1(C),XS(f)
        • S(f);N_GUARD::R1(C)
      • Refutation
        • R(d);P_PINQ(F)
    • Try
      • B(A);CHECK
      • Refutation
        • S(a);XB(A)
    • Try
      • B(A);CHECK
      • Vars
        • K(c);N_SPINB(b),S_FLIGHT::QAR2(F)
      • Refutation
        • S(a);XB(A)
    • Try
      • R(C);CHECK
      • Vars
        • K(c);N_SPINB(b),S_FLIGHT::QAB1(F)
      • Refutation
        • K(c);N_SPINB(b),S_FLIGHT
    • Try
      • R(C);
      • Threat
        • QAB1(F)
      • Vars
        • K(c);N_SPINB(b),S_FLIGHT,XR(C)::QAR2(F)
        • P(h);SBLOCK,XR(C)::S(D)
        • S(f);N_GUARD,N_SPINB(b)::R1(C),XS(f)
      • Refutation
        • R(d);
    • Try
      • R(E);CHECK,XB(b)
      • Refutation
        • Q(e);XR(E)
  • Actual
    • R(C);
    • Threat
      • QAR2(F)
    • Vars
      • P(i);CHECK,SBLOCK::QAR(F)
      • K(c);N_SPINB(b),P-FLIGHT::B(B)+R(C)
      • K(c);N_SPINB(b),S_FLIGHT::QAR2(F)
      • S(a);N_GUARD::QAB1(F)
      • S(a);N_GUARD::QAB1(F),XS(a)
      • S(f);N_GUARD::QAR1(F)
      • S(f);N_GUARD,N_SPINB(b)::QAR1(F),XS(f)
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