MESON Chess Problem Database

Problem Display
PID: 199969 (Qn6/4Rp2/1Bn5/1P1kPBp1/2p1p1K1/8/8/8 w - - 0 1)

Robins, Ernest

The Observer, 1947

(First published on Sun Jan 12 1947)

Qn6/4Rp2/1Bn5/1P1kPBp1/2p1p1K1/8/8/8

#2

7 + 7

15239 Valois Notebooks 2019

SOLUTION

  • SOUND
  • Sets
    • 1...Sa6
      • 2.Qxc6#
    • 1...Sd7
      • 2.Qxc6#
    • 1...c3
      • 2.Qa2#
  • Tries
    • 1.Be3?
      • 1...c3
        • 2.Qa2#
      • 1...Sa6
        • 2.Qxc6#
      • 1...Sd7
        • 2.Qxc6#
      • 1...f6!
  • Keys
    • 1.Qa1!
      • 1...Sxe5+
        • 2.Qxe5#
      • 1...Sxe7
        • 2.Qd4#
      • 1...c3
        • 2.Qa2#
      • 1...e3
        • 2.Qh1#
      • 1...Sb4
        • 2.Qd4#
      • 1...Sd4
        • 2.Qxd4#
      • 1...Sa5
        • 2.Qd4#
        • 2.Qd1#
      • 1...Sa7
        • 2.Qd4#
        • 2.Qd1#
      • 1...Sd8
        • 2.Qd4#
        • 2.Qd1#
      • 1...Sa6
        • 2.Rd7#
      • 1...Sd7
        • 2.Rxd7#
      • 1...f6
        • 2.Be6#

FEATURES

  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 2
    • ADDED MATES = 6
    • REMOVED MATES = 0
  • Sets
    • S(g);N_GUARD::QAB1(G),XS(e)
    • P(a);OGATEB::QAB(G)
  • Tries
    • Try
      • B(E);
      • Vars
        • P(a);OGATEB::QAB(G)
        • S(g);N_GUARD::QAB1(G),XS(e)
      • Refutation
        • P(f);
  • Actual
    • Q(G);N_PINS(e)
    • Vars
      • S(e);CHECK,OGATE,XP(C)::QAR1(G),XS(e)
      • S(e);N_GUARD,XR(F)::QAR1(G)
      • P(a);OGATEB::QAB(G)
      • P(b);OGATEB::QAB(G)
      • S(e);N_GUARD::QAR1(G)
      • S(e);N_GUARD::QAR1(G),XS(e)
      • S(g);N_GUARD::R(F)
      • S(g);N_GUARD::R(F),XS(g)
      • P(f);N_GUARD::B(D)
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