MESON Chess Problem Database

Problem Display
PID: 512 (8/2N5/2p1p3/4P3/2k1N3/K1P2p2/1n1QnP2/bR6 w - - 0 1)

Stevenson, Edward

The Observer, 1957

8/2N5/2p1p3/4P3/2k1N3/K1P2p2/1n1QnP2/bR6

#2

8 + 7

3639 Hastings Solving Ty. 2001-2002

SOLUTION

  • SOUND
  • Sets
    • 1...Sd1
      • 2.Rb4#
    • 1...Sd3
      • 2.Qa2#
    • 1...Sa4
      • 2.Rb4#
    • 1...Sc1
      • 2.Qd4#
    • 1...Sg1
      • 2.Qd4#
    • 1...Sxc3
      • 2.Qxc3#
    • 1...Sg3
      • 2.Qd4#
    • 1...Sd4
      • 2.Qxd4#
    • 1...Sf4
      • 2.Qd4#
    • 1...c5
      • 2.Sd6#
  • Tries
    • 1.Rd1?
      • 1...Sxc3
        • 2.Qxc3#
        • 2.Qd4#
      • 1...Sd3
        • 2.Qa2#
        • 2.Qxd3#
      • 1...Sa4
        • 2.Qa2#
        • 2.Qd3#
      • 1...Sc1
        • 2.Qd4#
      • 1...Sg1
        • 2.Qd4#
      • 1...Sg3
        • 2.Qd4#
      • 1...Sd4
        • 2.Qxd4#
      • 1...Sf4
        • 2.Qd4#
      • 1...c5
        • 2.Sd6#
      • 1...Sxd1!
    • 1.Rxb2?
      • threat
        • 2.Rb4#
      • 1...c5
        • 2.Sd6#
      • 1...Bxb2+!
    • 1.Qe3?
      • threat
        • 2.Sd2#
        • 2.Sd6#
      • 1...Sd4
        • 2.Qxd4#
      • 1...Sd3!
    • 1.Qxe2+?
      • 1...Sd3
        • 2.Rb4#
        • 2.Qa2#
      • 1...fxe2!
    • 1.Qd7?
      • 1...Sd4
        • 2.Qxd4#
      • 1...Sd1
        • 2.Rb4#
      • 1...Sd3
        • 2.Qxe6#
      • 1...Sa4
        • 2.Rb4#
      • 1...Sc1
        • 2.Qd4#
      • 1...Sg1
        • 2.Qd4#
      • 1...Sg3
        • 2.Qd4#
      • 1...Sf4
        • 2.Qd4#
      • 1...c5
        • 2.Qb5#
      • 1...Sxc3!
  • Keys
    • 1.Qd6!
      • 1...Sxc3
        • 2.Sd2#
      • 1...Sd4
        • 2.Qxd4#
      • 1...Sd1
        • 2.Rb4#
      • 1...Sd3
        • 2.Qxe6#
      • 1...Sa4
        • 2.Rb4#
      • 1...Sc1
        • 2.Qd4#
      • 1...Sg1
        • 2.Qd4#
      • 1...Sg3
        • 2.Qd4#
      • 1...Sf4
        • 2.Qd4#
      • 1...c5
        • 2.Qa6#

FEATURES

  • Static
    • TYPE = MUTATE
    • CHANGED MATES = 3
    • ADDED MATES = 0
    • REMOVED MATES = 0
  • Sets
    • S(b);OGATE::R1(A)
    • S(b);OGATE,SBLOCK::QAB(B)
    • S(c);N_GUARD::QAR1(B)
    • S(c);OGATE,XP(E)::QAR1(B),XS(c)
    • S(c);N_GUARD::QAR1(B),XS(c)
    • P(f);SBLOCK::S(F)
  • Tries
    • Try
      • R(A);
      • Vars
        • S(c);N_GUARD::QAR1(B)
        • S(c);N_GUARD::QAR1(B),XS(c)
        • P(f);SBLOCK::S(F)
      • Refutation
        • S(b);XR(A)
    • Try
      • R(A);XS(b)
      • Threat
        • R1(A)
      • Vars
        • P(f);SBLOCK::S(F)
      • Refutation
        • B(a);CHECK,XR(A)
    • Try
      • Q(B);
      • Threat
        • DUALS(2)
      • Vars
        • S(c);N_GUARD::QAR1(B),XS(c)
      • Refutation
        • S(b);
    • Try
      • Q(B);CHECK,XS(c)
      • Refutation
        • P(d);XQ(B)
    • Try
      • Q(B);
      • Vars
        • S(c);N_GUARD::QAR1(B),XS(c)
        • S(b);OGATE::R1(A)
        • S(b);SBLOCK::QAB(B),XP(g)
        • S(c);N_GUARD::QAR1(B)
        • P(f);OGATE::QAB1(B)
      • Refutation
        • S(c);XP(E)
  • Actual
    • Q(B);
    • Vars
      • S(c);SBLOCK,XP(E)::S(F)
      • S(c);N_GUARD::QAR1(B),XS(c)
      • S(b);OGATE::R1(A)
      • S(b);SBLOCK::QAB(B),XP(g)
      • S(c);N_GUARD::QAR1(B)
      • P(f);OGATE::QAB(B)
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