MESON Chess Problem Database

Problem Display
PID: 201039 (2r5/1n4rp/R2q2kp/3Q3p/3nP2P/1B2p3/4N3/2bK1R2 w - - 0 1)

Starling, WL

The Observer, 1949

(First published on Sun Jun 12 1949)

2r5/1n4rp/R2q2kp/3Q3p/3nP2P/1B2p3/4N3/2bK1R2

#2

8 + 11

15239 Valois Notebooks 2020

SOLUTION

  • SOUND
  • Sets
    • 1...Qf6
      • 2.Sf4#
      • 2.Rg1#
      • 2.Rfxf6#
      • 2.Raxf6#
    • 1...Rf7
      • 2.Qxf7#
    • 1...Rgg8
      • 2.Qf7#
  • Tries
    • 1.Rf6+?
      • 1...Qxf6
        • 2.Sf4#
      • 1...Kxf6!
    • 1.Rxd6+?
      • 1...Se6
        • 2.Rxe6#
        • 2.Qxe6#
        • 2.Qf5#
      • 1...Sxd6!
    • 1.Qxd6+?
      • 1...Se6
        • 2.Qg3#
        • 2.Qxe6#
      • 1...Sxd6!
  • Keys
    • 1.e5!
      • threat
        • 2.Qg2#
      • 1...Sxe2
        • 2.Qd3#
      • 1...Sxb3
        • 2.Qd3#
      • 1...Sf3
        • 2.Qd3#
      • 1...Sc2
        • 2.Qd3#
      • 1...Sb5
        • 2.Qd3#
      • 1...Sf5
        • 2.Sf4#
      • 1...Sc6
        • 2.Bc2#
      • 1...Se6
        • 2.Rf6#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 0
    • ADDED MATES = 8
    • REMOVED MATES = 2
  • Sets
    • R(i);N_GUARD::QAB1(G),XR(i)
    • R(i);N_GUARD::QAB1(G)
  • Tries
    • Try
      • R(B);CHECK,N_PINQ(e)
      • Vars
        • Q(e);P_SPINQ(e),XR(B)::S(C)
      • Refutation
        • K(f);P-FLIGHT,P_SPINQ(e),XR(B)
    • Try
      • R(H);CHECK,XQ(e)
      • Refutation
        • S(h);XR(H)
    • Try
      • Q(G);CHECK,XQ(e)
      • Refutation
        • S(h);P_SPINS(h),XQ(G)
  • Actual
    • P(E);
    • Threat
      • QAR(G)
    • Vars
      • S(c);OGATE,P_PINQ(G),XS(C)::QAB(G)
      • S(c);OGATE,P_PINQ(G),XB(D)::QAB(G)
      • S(c);OGATE,P_PINQ(G)::QAB(G)
      • S(c);P_PINQ(G),SBLOCK::S(C)
      • S(c);N_GUARD,N_SPINQ(e),P_PINQ(G),S_CUTR(k)::B(D)
      • S(c);N_SPINQ(e),P_PINQ(G),S_CUTQ(e)::R1(B)
HTML5 logo

Developed and maintained by Brian Stephenson.
Implemented with HTML5, MySQL, Perl (with, inter alia, CGI::Simple, HTML::Template & XML::LibXML) & CSS/Javascript (jQuery, Bootstrap & DataTables).