MESON Chess Problem Database

Problem Display
PID: 21805 (8/5p2/Q4Pp1/Prp1P1K1/1PkPP3/R2N1N2/8/8 w - - 0 1)

Larsen, Karl Adolf Koefoed

4th HM., Good Companions (April Complete Blocks), 1921

8/5p2/Q4Pp1/Prp1P1K1/1PkPP3/R2N1N2/8/8

#2

11 + 5

3132 The Good Companion Two-Mover 1922
3098 FIDE Album (1914-1944) (I) 1971
15593 170 Skakopgaver (Jorgensen) 1975
133 The Problemist Supplement 2017

SOLUTION

  • SOUND
  • Sets
    • 1...cxb4
      • 2.Sb2#
    • 1...cxd4
      • 2.Sd2#
  • Tries
    • 1.Kf4?
      • 1...cxb4
        • 2.Sb2#
      • 1...cxd4
        • 2.Sd2#
      • 1...g5+!
    • 1.Kg4?
      • 1...cxb4
        • 2.Sb2#
      • 1...cxd4
        • 2.Sd2#
      • 1...g5!
    • 1.Kh4?
      • 1...cxb4
        • 2.Sb2#
      • 1...cxd4
        • 2.Sd2#
      • 1...g5+!
    • 1.Kh6?
      • 1...cxb4
        • 2.Sb2#
      • 1...cxd4
        • 2.Sd2#
      • 1...g5!
    • 1.Qc8?
      • 1...Rxb4
        • 2.Qxc5#
      • 1...Rb6
        • 2.Qxc5#
      • 1...Rb7
        • 2.Qxc5#
      • 1...Rb8
        • 2.Qxc5#
      • 1...Rxa5!
    • 1.Qb6?
      • 1...Rxb4
        • 2.Qxc5#
      • 1...Rxa5
        • 2.Sb2#
      • 1...cxb4
        • 2.Sb2#
        • 2.Sd2#
      • 1...cxd4
        • 2.Sd2#
        • 2.Qxd4#
      • 1...Rxb6!
    • 1.Qc6?
      • threat
        • 2.Qd5#
      • 1...Rxb4
        • 2.Qxc5#
      • 1...Rb6
        • 2.Qxc5#
      • 1...Rb7
        • 2.Qxc5#
      • 1...Rb8
        • 2.Qxc5#
      • 1...Rxa5!
    • 1.Qd6?
      • threat
        • 2.Sd2#
        • 2.Qd5#
      • 1...Rxb4
        • 2.Qxc5#
      • 1...cxb4
        • 2.Sb2#
        • 2.Sd2#
      • 1...cxd4
        • 2.Sb2#
        • 2.Sd2#
        • 2.Qxd4#
      • 1...Rb6
        • 2.Qxc5#
      • 1...Rb7
        • 2.Qxc5#
      • 1...Rb8
        • 2.Qxc5#
      • 1...Rxa5!
  • Keys
    • 1.e6!
      • 1...cxb4+
        • 2.Sde5#
      • 1...cxd4+
        • 2.Sfe5#
      • 1...fxe6
        • 2.Qxe6#

FEATURES

  • Static
    • TYPE = MUTATE
    • CHANGED MATES = 2
    • ADDED MATES = 1
    • REMOVED MATES = 0
  • Sets
    • P(c);P_PINP(H),SBLOCK,XP(D)::S(B)
    • P(c);P_PINP(H),SBLOCK,XP(E)::S(C)
  • Tries
    • Try
      • K(I);S_FLIGHT
      • Vars
        • P(c);SBLOCK,XP(D)::S(B)
        • P(c);SBLOCK,XP(E)::S(C)
      • Refutation
        • P(d);CHECK
    • Try
      • K(I);P-FLIGHT
      • Vars
        • P(c);SBLOCK,XP(D)::S(B)
        • P(c);SBLOCK,XP(E)::S(C)
      • Refutation
        • P(d);
    • Try
      • K(I);S_FLIGHT
      • Vars
        • P(c);SBLOCK,XP(D)::S(B)
        • P(c);SBLOCK,XP(E)::S(C)
      • Refutation
        • P(d);CHECK
    • Try
      • K(I);S_FLIGHT
      • Vars
        • P(c);SBLOCK,XP(D)::S(B)
        • P(c);SBLOCK,XP(E)::S(C)
      • Refutation
        • P(d);
    • Try
      • Q(J);N_PINR(b),P_PINP(c)
      • Vars
        • R(b);N_GUARD,XP(D)::QAR1(J),XP(c)
        • R(b);N_GUARD::QAR1(J),XP(c)
      • Refutation
        • R(b);XP(G)
    • Try
      • Q(J);N_PINR(b)
      • Vars
        • R(b);N_GUARD,XP(D)::QAR1(J),XP(c)
        • R(b);XP(G)::S(B)
      • Refutation
        • R(b);XQ(J)
    • Try
      • Q(J);N_PINR(b),P_PINP(c)
      • Threat
        • QAB1(J)
      • Vars
        • R(b);N_GUARD,XP(D)::QAR1(J),XP(c)
        • R(b);N_GUARD::QAR1(J),XP(c)
      • Refutation
        • R(b);XP(G)
    • Try
      • Q(J);N_PINR(b)
      • Threat
        • DUALS(2)
      • Vars
        • R(b);N_GUARD,XP(D)::QAR1(J),XP(c)
        • R(b);N_GUARD::QAR1(J),XP(c)
      • Refutation
        • R(b);XP(G)
  • Actual
    • P(H);
    • Vars
      • P(c);CHECK,SBLOCK,XP(D)::S(B)
      • P(c);CHECK,SBLOCK,XP(E)::S(C)
      • P(e);OGATE,XP(H)::QAB(J),XP(e)
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