MESON Chess Problem Database

Problem Display
PID: 139416 (4N3/Qp2p2r/6R1/1PPk4/Nb3BR1/1Pr2np1/K1n1P2q/1B6 w - - 0 1)

Harley, Brian

The Observer, 1930

(First published on Sun May 11 1930)

4N3/Qp2p2r/6R1/1PPk4/Nb3BR1/1Pr2np1/K1n1P2q/1B6

#2

12 + 10

56 The Problemist 1937
15290 Harley Scrapbook 2014
15239 Valois Notebooks 2018

SOLUTION

  • SOUND
  • Sets
    • 1...Scd4
      • 2.Sc7#
  • Tries
    • 1.Bxg3?
      • threat
        • 2.Sc7#
        • 2.Qxb7#
      • 1...Rxc5
        • 2.Sb6#
      • 1...Ba5
        • 2.Qxb7#
      • 1...Scd4
        • 2.Sc7#
        • 2.Be4#
      • 1...Sfd4
        • 2.Sc7#
        • 2.e4#
      • 1...Se5
        • 2.Sc7#
      • 1...b6
        • 2.Sc7#
        • 2.Qb7#
        • 2.Qd7#
        • 2.Qa8#
      • 1...e5
        • 2.Rd6#
      • 1...e6
        • 2.Sf6#
      • 1...Qxg3!
    • 1.Bd6?
      • threat
        • 2.Sb6#
        • 2.Sc7#
        • 2.Qxb7#
      • 1...Rxc5
        • 2.Sb6#
      • 1...Bxc5
        • 2.Sxc3#
        • 2.Sc7#
        • 2.Qxb7#
      • 1...Ba5
        • 2.Qxb7#
      • 1...Scd4
        • 2.Sb6#
        • 2.Sc7#
        • 2.Be4#
      • 1...Sfd4
        • 2.Sb6#
        • 2.Sc7#
        • 2.e4#
      • 1...Se5
        • 2.Sb6#
        • 2.Sc7#
      • 1...b6
        • 2.Sxb6#
        • 2.Sc7#
        • 2.Qb7#
        • 2.Qa8#
      • 1...e5
        • 2.Sb6#
      • 1...e6
        • 2.Sb6#
        • 2.Sf6#
      • 1...exd6!
    • 1.Bc7?
      • threat
        • 2.Qxb7#
      • 1...Rxc5
        • 2.Sb6#
      • 1...Scd4
        • 2.Be4#
      • 1...Sfd4
        • 2.e4#
      • 1...b6
        • 2.Qb7#
        • 2.Qa8#
      • 1...Se5!
  • Keys
    • 1.Bb8!
      • threat
        • 2.Qxb7#
      • 1...Rxc5
        • 2.Sb6#
      • 1...Scd4
        • 2.Be4#
      • 1...Sfd4
        • 2.e4#
      • 1...Se5
        • 2.Sc7#
      • 1...b6
        • 2.Qb7#
        • 2.Qd7#
        • 2.Qa8#
      • 1...e5
        • 2.Rd6#
      • 1...e6
        • 2.Sf6#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 1
    • ADDED MATES = 5
    • REMOVED MATES = 0
  • Sets
    • S(a);P_PINP(C),SBLOCK::S(L)
  • Tries
    • Try
      • B(F);XP(e)
      • Threat
        • DUALS(2)
      • Vars
        • R(c);SBLOCK,XP(I)::S(E)
        • B(f);::QAB(K),XP(h)
        • S(d);::S(L)
        • P(i);N_GUARD::R1(J)
        • P(i);N_GUARD,SBLOCK::S(L)
      • Refutation
        • Q(b);XB(F)
    • Try
      • B(F);
      • Threat
        • DUALS(3)
      • Vars
        • R(c);XP(I)::S(E)
        • B(f);::QAB(K),XP(h)
        • P(i);::S(E)
      • Refutation
        • P(i);XB(F)
    • Try
      • B(F);
      • Threat
        • QAB(K),XP(h)
      • Vars
        • R(c);SBLOCK,XP(I)::S(E)
        • S(a);OGATE,P_PINP(C),SBLOCK::B(A)
        • S(d);SBLOCK::P(C)
      • Refutation
        • S(d);
  • Actual
    • B(F);
    • Threat
      • QAB(K),XP(h)
    • Vars
      • R(c);SBLOCK,XP(I)::S(E)
      • S(a);OGATE,P_PINP(C),SBLOCK::B(A)
      • S(d);SBLOCK::P(C)
      • S(d);SBLOCK::S(L)
      • P(i);N_GUARD,SBLOCK::R1(J)
      • P(i);N_GUARD,SBLOCK::S(L)
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