MESON Chess Problem Database
Problem Display
PID: 196280 (3R4/5NK1/4pPQ1/5p1p/4kpnR/1nP5/4P1rp/5N1B w - - 0 1)
Sher, H
The Observer, 1943
(First published on Sun Mar 7 1943)
#2
10 + 9
| 15239 | Valois Notebooks | 2019 |
SOLUTION
- SOUND
- Sets
- 1...Sa1
- 2.Rd4#
- 1...Sc1
- 2.Rd4#
- 1...Sd2
- 2.Rd4#
- 1...Sd4
- 2.Rxd4#
- 1...Sa5
- 2.Rd4#
- 1...Sc5
- 2.Rd4#
- 1...Sf2
- 2.Bxg2#
- 2.Qxg2#
- 1...Se3
- 2.Sg3#
- 1...Se5
- 2.Sg5#
- 1...Sxf6
- 2.Bxg2#
- 2.Qxg2#
- 1...Sh6
- 2.Bxg2#
- 2.Qxg2#
- 1...e5
- 2.Sg5#
- 1...Sa1
- Tries
- 1.Kf8?
- 1...Sxf6
- 2.Bxg2#
- 2.Qxg2#
- 1...Sa1
- 2.Rd4#
- 1...Sc1
- 2.Rd4#
- 1...Sd2
- 2.Rd4#
- 1...Sd4
- 2.Rxd4#
- 1...Sa5
- 2.Rd4#
- 1...Sc5
- 2.Rd4#
- 1...Sf2
- 2.Bxg2#
- 2.Qxg2#
- 1...Se3
- 2.Sg3#
- 1...Se5
- 2.Sg5#
- 1...Sh6
- 2.Bxg2#
- 2.Qxg2#
- 1...e5
- 2.Sg5#
- 1...f3!
- 1...Sxf6
- 1.Kh8?
- 1...Sxf6
- 2.Bxg2#
- 2.Qxg2#
- 1...Sa1
- 2.Rd4#
- 1...Sc1
- 2.Rd4#
- 1...Sd2
- 2.Rd4#
- 1...Sd4
- 2.Rxd4#
- 1...Sa5
- 2.Rd4#
- 1...Sc5
- 2.Rd4#
- 1...Sf2
- 2.Bxg2#
- 2.Qxg2#
- 1...Se3
- 2.Sg3#
- 1...Se5
- 2.Sg5#
- 1...Sh6
- 2.Bxg2#
- 2.Qxg2#
- 1...e5
- 2.Sg5#
- 1...f3!
- 1...Sxf6
- 1.Rxg4?
- threat
- 2.Bxg2#
- 1...Sd2
- 2.Rd4#
- 1...Sd4
- 2.Rxd4#
- 1...hxg4!
- threat
- 1.Rd3?
- 1...Sxf6
- 2.Sg3#
- 2.Bxg2#
- 2.Qxg2#
- 1...Sd4
- 2.Rxd4#
- 1...Sa1
- 2.Sd2#
- 2.Rd4#
- 1...Sc1
- 2.Sd2#
- 2.Rd4#
- 1...Sd2
- 2.Sxd2#
- 2.Rd4#
- 1...Sa5
- 2.Sd2#
- 2.Rd4#
- 1...Sc5
- 2.Sd2#
- 2.Rd4#
- 1...Sf2
- 2.Sg3#
- 2.Bxg2#
- 2.Qxg2#
- 1...Se3
- 2.Sg3#
- 1...Se5
- 2.Sg3#
- 2.Sg5#
- 2.Sd6#
- 1...Sh6
- 2.Sg3#
- 2.Bxg2#
- 2.Qxg2#
- 1...e5
- 2.Sg5#
- 2.Sd6#
- 1...f3!
- 1...Sxf6
- 1.Rd6?
- 1...Sxf6
- 2.Bxg2#
- 2.Qxg2#
- 1...Sa1
- 2.Rd4#
- 1...Sc1
- 2.Rd4#
- 1...Sd2
- 2.Rd4#
- 1...Sd4
- 2.Rxd4#
- 1...Sa5
- 2.Rd4#
- 1...Sc5
- 2.Rd4#
- 1...Sf2
- 2.Bxg2#
- 2.Qxg2#
- 1...Se3
- 2.Sg3#
- 1...Se5
- 2.Sg5#
- 1...Sh6
- 2.Bxg2#
- 2.Qxg2#
- 1...e5
- 2.Sg5#
- 1...f3!
- 1...Sxf6
- 1.Rd7?
- 1...Sxf6
- 2.Bxg2#
- 2.Qxg2#
- 1...Sa1
- 2.Rd4#
- 1...Sc1
- 2.Rd4#
- 1...Sd2
- 2.Rd4#
- 1...Sd4
- 2.Rxd4#
- 1...Sa5
- 2.Rd4#
- 1...Sc5
- 2.Rd4#
- 1...Sf2
- 2.Bxg2#
- 2.Qxg2#
- 1...Se3
- 2.Sg3#
- 1...Se5
- 2.Sg5#
- 1...Sh6
- 2.Bxg2#
- 2.Qxg2#
- 1...e5
- 2.Sg5#
- 1...f3!
- 1...Sxf6
- 1.Qxh5?
- 1...Sf2+
- 2.Bxg2#
- 1...Se3+
- 2.Sg3#
- 1...Se5+
- 2.Sg5#
- 1...Sxf6+
- 2.Bxg2#
- 1...Sh6+
- 2.Bxg2#
- 1...Sa1
- 2.Rd4#
- 1...Sc1
- 2.Rd4#
- 1...Sd2
- 2.Rd4#
- 1...Sd4
- 2.Rxd4#
- 1...Sa5
- 2.Rd4#
- 1...Sc5
- 2.Rd4#
- 1...e5
- 2.Sg5#
- 1...f3!
- 1...Sf2+
- 1.Qh7?
- 1...Sf2+
- 2.Bxg2#
- 1...Se3+
- 2.Sg3#
- 1...Se5+
- 2.Sg5#
- 1...Sxf6+
- 2.Bxg2#
- 1...Sh6+
- 2.Bxg2#
- 1...Sa1
- 2.Rd4#
- 1...Sc1
- 2.Rd4#
- 1...Sd2
- 2.Rd4#
- 1...Sd4
- 2.Rxd4#
- 1...Sa5
- 2.Rd4#
- 1...Sc5
- 2.Rd4#
- 1...e5
- 2.Sg5#
- 1...f3!
- 1...Sf2+
- 1.Qg5?
- 1...Sxf6
- 2.Bxg2#
- 2.Rxf4#
- 2.Qxg2#
- 1...Sa1
- 2.Rd4#
- 1...Sc1
- 2.Rd4#
- 1...Sd2
- 2.Rd4#
- 1...Sd4
- 2.Rxd4#
- 1...Sa5
- 2.Rd4#
- 1...Sc5
- 2.Rd4#
- 1...Sf2
- 2.Bxg2#
- 2.Rxf4#
- 2.Qxg2#
- 1...Se3
- 2.Sg3#
- 2.Rxf4#
- 1...Se5
- 2.Rxf4#
- 1...Sh6
- 2.Bxg2#
- 2.Rxf4#
- 2.Qxg2#
- 1...f3
- 2.Qe3#
- 1...e5!
- 1...Sxf6
- 1.Kf8?
- Keys
- 1.Qh6!
- 1...Sf2+
- 2.Bxg2#
- 1...Se3+
- 2.Sg3#
- 1...Se5+
- 2.Sg5#
- 1...Sxf6+
- 2.Bxg2#
- 1...Sxh6+
- 2.Bxg2#
- 1...Sa1
- 2.Rd4#
- 1...Sc1
- 2.Rd4#
- 1...Sd2
- 2.Rd4#
- 1...Sd4
- 2.Rxd4#
- 1...Sa5
- 2.Rd4#
- 1...Sc5
- 2.Rd4#
- 1...f3
- 2.Qe3#
- 1...e5
- 2.Sg5#
- 1...Sf2+
- 1.Qh6!
FEATURES
- Static
- TYPE = INCOMPLETE_BLOCK
- CHANGED MATES = 0
- ADDED MATES = 4
- REMOVED MATES = 0
- Sets
- S(c);N_GUARD::R1(J)
- S(c);N_GUARD::R1(J),XS(c)
- S(f);N_SPINP(g),P_PINQ(G),P_SPINP(e),SBLOCK::S(A)
- S(f);N_SPINP(g),P_PINQ(G),P_SPINP(e),SBLOCK::S(H)
- P(i);SBLOCK::S(H)
- Tries
- Try
- K(I);S_FLIGHT
- Vars
- S(c);N_GUARD::R1(J)
- S(c);N_GUARD::R1(J),XS(c)
- S(f);N_SPINP(g),P_SPINP(e),SBLOCK::S(A)
- S(f);N_SPINP(g),P_SPINP(e),SBLOCK::S(H)
- P(i);SBLOCK::S(H)
- Refutation
- P(e);N_SPINR(a),P_SPINS(f)
- Try
- K(I);S_FLIGHT
- Vars
- S(c);N_GUARD::R1(J)
- S(c);N_GUARD::R1(J),XS(c)
- S(f);N_SPINP(g),P_SPINP(e),SBLOCK::S(A)
- S(f);N_SPINP(g),P_SPINP(e),SBLOCK::S(H)
- P(i);SBLOCK::S(H)
- Refutation
- P(e);N_SPINR(a),P_SPINS(f)
- Try
- R(E);N_PINP(g),P_PINP(e),XS(f)
- Threat
- B(B),XR(a)
- Vars
- S(c);N_GUARD::R1(J)
- S(c);N_GUARD::R1(J),XS(c)
- Refutation
- P(h);N_SPINP(e),P_SPINP(g),XR(E)
- Try
- R(J);
- Vars
- S(c);N_GUARD::R1(J),XS(c)
- S(f);N_SPINP(g),P_PINQ(G),P_SPINP(e)::S(A)
- Refutation
- P(e);N_SPINR(a),P_SPINS(f)
- Try
- R(J);
- Vars
- S(c);N_GUARD::R1(J)
- S(c);N_GUARD::R1(J),XS(c)
- S(f);N_SPINP(g),P_PINQ(G),P_SPINP(e),SBLOCK::S(A)
- S(f);N_SPINP(g),P_PINQ(G),P_SPINP(e),SBLOCK::S(H)
- P(i);SBLOCK::S(H)
- Refutation
- P(e);N_SPINR(a),P_SPINS(f)
- Try
- R(J);
- Vars
- S(c);N_GUARD::R1(J)
- S(c);N_GUARD::R1(J),XS(c)
- S(f);N_SPINP(g),P_PINQ(G),P_SPINP(e),SBLOCK::S(A)
- S(f);N_SPINP(g),P_PINQ(G),P_SPINP(e),SBLOCK::S(H)
- P(i);SBLOCK::S(H)
- Refutation
- P(e);N_SPINR(a),P_SPINS(f)
- Try
- Q(G);N_PINP(g),XP(h)
- Vars
- S(f);CHECK,P_SPINP(e)::B(B),XR(a)
- S(f);CHECK,P_SPINP(e),SBLOCK::S(A)
- S(f);CHECK,P_SPINP(e),SBLOCK::S(H)
- S(f);CHECK,P_SPINP(e),XP(F)::B(B),XR(a)
- S(c);N_GUARD::R1(J)
- S(c);N_GUARD::R1(J),XS(c)
- P(i);SBLOCK::S(H)
- Refutation
- P(e);N_SPINR(a),P_SPINS(f)
- Try
- Q(G);
- Vars
- S(f);CHECK,N_SPINP(g),P_SPINP(e)::B(B),XR(a)
- S(f);CHECK,N_SPINP(g),P_SPINP(e),SBLOCK::S(A)
- S(f);CHECK,N_SPINP(g),P_SPINP(e),SBLOCK::S(H)
- S(f);CHECK,N_SPINP(g),P_SPINP(e),XP(F)::B(B),XR(a)
- S(c);N_GUARD::R1(J)
- S(c);N_GUARD::R1(J),XS(c)
- P(i);SBLOCK::S(H)
- Refutation
- P(e);N_SPINR(a),P_SPINS(f)
- Try
- Q(G);N_PINP(g)
- Vars
- S(c);N_GUARD::R1(J)
- S(c);N_GUARD::R1(J),XS(c)
- S(f);OGATE,P_PINQ(G),P_SPINP(e)::R1(E),XP(e)
- P(e);N_SPINR(a),OGATE,P_SPINS(f)::QAR1(G)
- Refutation
- P(i);
- Try
- Actual
- Q(G);N_PINP(g)
- Vars
- S(f);CHECK,P_SPINP(e)::B(B),XR(a)
- S(f);CHECK,P_SPINP(e),SBLOCK::S(A)
- S(f);CHECK,P_SPINP(e),SBLOCK::S(H)
- S(f);CHECK,P_SPINP(e),XP(F)::B(B),XR(a)
- S(f);CHECK,P_SPINP(e),XQ(G)::B(B),XR(a)
- S(c);N_GUARD::R1(J)
- S(c);N_GUARD::R1(J),XS(c)
- P(e);N_SPINR(a),OGATE,P_SPINS(f)::QAR1(G)
- P(i);SBLOCK::S(H)
Developed and maintained by Brian Stephenson.
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