# StrateGems

No. 53, Jan-Mar 2011

R0174 -

StrateGems, No. 53, Jan-Mar 2011

4+6. -6 & #1 (Proca, Anti-Circe)

[3k4/8/4r3/2q5/1K3N2/2p5/1b6/R4r1R]

Solution

Retract: -1.Ra8xSa2(+wRh1)! Sc1-a2+ -2.Ra1xBa3(+wRa1) Qf8-c5+ -3.a7xRb8R(+wRa1) Rc8-b8+ -4.Kc5-b4 Rb8-c8+ -5.Kb6-c5 Qh8-f8+ -6.Sg6-f4 & 1.axb8Q(+wQd1)#

R0175 -

StrateGems, No. 53, Jan-Mar 2011

13+13. Add a piece and release the position

[1B6/prpb2p1/2KPp3/qp1p4/Q1k5/nRP3p1/BRPP2Pp/BN6]

Solution

Add a wBb4. Retract: -1.Bc8-d7+ e5xBd6 -2.Bc5-d6 [The tempo-play works fine after -2.Bf8-d6? e4-e5 -3.e7-e6 e3-e4 -4.B~-c8 Kd7-c6, but white cannot unpromote on f8. A black piece needs to be trapped first, so that white can perform a complex maneuver and then free it again] e4-e5 -3.Bb6-c5 e3-e4 -4.Qa6-a5 Qa5-a4 5.g4-g3 Bf8-b4 -6.g5-g4 f7-f8B -7.g6-g5 f6-f7 -8.f7xSg6 Sf4-g6 -9.h3-h2 Sd3-f4 -10.h4-h3 Sb4-d3 -11.h5-h4 Qa4-a5 -12.Qa5-a6 f5-f6 -13.Bc5-b6 f4-f5 -14.Bf8-c5 f3-f4 -15.e7-e6 f2-f3 -16.B~-c8 Kd7-c6

The last 30 single moves are precisely determined. Ability of pieces to visit and leave b4 and b6 is demonstrated. (A)

R0176 -

StrateGems, No. 53, Jan-Mar 2011

14+12. Last 40 single moves?

[8/4p3/N5p1/3PPPp1/2PRKNrb/2prQRk1/P1Bpp1Pn/1b3B2]

Solution

Retract: -1.Rf2xSf3+ b2-b1B -2.Ba4-c2! [-2.Sc7-a6? b3-b2 -3.Se8-c7 b4-b3 -4.Sd6-e8 b5-b4 -5.Sf7-d6 b6-b5 -6.Sh8-f7 b7-b6 -7.h7-h8S is one move too slow] b3-b2 -3.Bc6-a4 b4-b3 -4.Ba8-c6 b5-b4 -5.Sb4-a6 b6-b5 -6.Sc2-b4 b7-b6 -7.Se1-c2 Sg1-f3 -8.Sf3-e1+ Sh3-g2 -9.a7-a8B Sg1-h3 -10.a6-a7 Sh3-g1 -11.a5-a6 Sg1-h3 -12.a4-a5 Sh3-g1 -13.a3-a4 Sg1-h3 -14.b2xPa3 Sh3-g1 -15.Se6-f4 Sf4-h3+ -16.Sd8-e6 a4-a3 -17.Sf7-d8 a5-a4 -18.Sh8-f7 a6-a5 -19.h7-h8S a7-a6 -20.h6-h7 h7xSg6 -21.S-~ g6-g5

Two excelsiors followed by a light-squared Bishop promotion. (A)

P0287 -

StrateGems, No. 53, Jan-Mar 2011

15+15. PG 17½

[1n2k2r/1pp5/bpnp1p2/4p1br/7p/q1P5/PP1PPPPP/RNB1KBNR]

Solution

1.c3 h5 2.Qb3 h4 3.Qb6 axb6 4.Kd1 Ra5 5.Kc2 Rah5 6.Kd3 e5 7.Ke3 Be7 8.Ke4 Bg5 9.Kf5 f6 10.Kg6 Se7+ 11.Kxg7 Sec6 12.Kg6 Qe7 13.Kf5 Qa3 14.Ke4 d6 15.Kd3 Be6 16.Kc2 Bc4 17.Kd1 Ba6 18.Ke1

P0288 -

StrateGems, No. 53, Jan-Mar 2011

15+13. PG 18½ (2 variations)

[1nbqk1n1/1ppppp2/4B2R/3QN1P1/1rP2B2/1r2P2N/1pP2PP1/RN2K3]

Solution

1.h4 g5 2.hxg5 h6 3.Rxh6 Bg7 4.Sh3 Bc3 5.dxc3 a5 6.Bf4 a4 7.e3 a3 8.Bc4 axb2 and now: i) 9.Be6 Ra3 10.Qd5 Rb3 11.a4 Rh7 12.a5 Rg7 13.a6 Rg6 14.a7 Rf6 15.a8S Rf5 16.Sb6 Re5 17.Sc4 Re4 18.Se5 Reb4 19.c4 and ii) 9.a4 Ra6 10.a5 Rc6 11.a6 Rh7 12.a7 Rg7 13.a8S Rgg6 14.Sb6 Rgd6 15.Be6 Rd3 16.Sc4 Rb6 17.Se5 Rb4 18.c4 Rdb3 19.Qd5

Two distinct solutions with the Rooks switching and taking different paths. (A)

P0289 -

StrateGems, No. 53, Jan-Mar 2011

13+15. PG 19

[3n4/ppk1qppp/1rp2n1r/3pb3/4p3/5P2/PPPPPP1P/RNB3KR]

Solution

1.Sf3 d5 2.Se5 Bg4 3.Sd7 Bf3 4.gxf3 e5 5.Bh3 Bd6 6.Bf5 Qe7 7.Bd3 e4 8.Bb5 Be5 9.Bc6 Sxc6 10.Kf1 0-0-0 11.Sb8 Rd6 12.Kg1 Rh6 13.Qf1 Sf6 14.Qg2 Rd8 15.Qg5 Td6 16.Qe3 Sd8 17.Qb6 Rxb6 18.Sa6 c6 19.Sc7 Kxc7 6-move wS trip; 5-move wB trip; 5-move wQ trip. The star move is 11.Sb8!! (11.Sf6? blocks Rd6-h6 - 11.Sf8? blocks Rh8-d8 - 11.Sc5? blocks Qe3-b6).

Since the wS is captured on c7, all the avoided squares are legitimate "tries": each obstructs, and each can reach c7 in 2 moves. (A)

P0290 -

StrateGems, No. 53, Jan-Mar 2011

13+14. PG 19

[7k/3qpprb/n2r1np1/p2pb3/8/7p/2P1PPPP/RNBQKBNR]

Solution

1.d4 h5 2.d5 h4 3.d6 h3 4.dxc7 d5 5.a4 Bf5 6.a5 Bh7 7.a6 g6 8.axb7 a5 9.c8S Ra6 10.Sd6+ Rxd6 11.b4 Sa6 12.b8S Bg7 13.Sd7 Be5 14.Sf6+ Sxf6 15.b5 0-0 16.b6 Kh8 17.b7 Rg8 18.b8S Rg7 19.Sd7 Qxd7 Three Ceriani-Frolkin Knights are captured by pieces (not by pawns). (A).

See also P0008496 and P1098633 in PDB: http://www.softdecc.com/pdb/index.pdb and in particular, Silvio Baier’s P1185369 with the additional effect that the three pawns promote on the same square and the three Knights are captured on the same square.

P0291 -

StrateGems, No. 53, Jan-Mar 2011

13+12. PG 20

[rnbqkbnr/pPpp2p1/B7/6B1/K6P/PN1P1R2/2PR1P1N/8]

Solution

1.a4 f5 2.a5 f4 3.a6 f3 4.axb7 fxe2 5.Sf3 exd1B 6.Ba6 h5 7.d3 h4 8.Bg5 h3 9.Sbd2 hxg2 10.h4 g1B 11.Rh3 Bh2 12.Sxh2 Bf3 13.Rxf3 e5 14.0-0-0 Ba3 15.bxa3 e4 16.Kb2 e3 17.Kb3 e2 18.Ka4 e1B 19.Sb3 Bb4 20.Rd2 Bf8

One Pronkin and two Ceriani-Frolkin Bishops without doubled pawns or visible promotee. (A)

P0292 -

StrateGems, No. 53, Jan-Mar 2011

14+13. PG 22½

[rnbq3r/p2pn2p/3bk3/1B5p/pP2P3/1PN1P3/PBQ2K1P/R5NR]

Solution

1.f4 c5 2.f5 c4 3.f6 c3 4.fxe7 f5 5.g4 Kf7 6.e8B+ Ke6 7.Bh5 g6 8.g5 gxh5 9.g6 Bd6 10.g7 Se7 11.g8R f4 12.Rg4 f3 13.Ra4 b5 14.e4 bxa4 15.Bb5 f2+ 16.Ke2 f1B+ 17.Kf2 Bc4 18.b4 Bb3 19.cxb3 c2 20.Bb2 c1R 21.Qc2 Re1 22.Sc3 Re3 23.dxe3

Proof game of the future with mixed Ceriani-Frolkin pieces (RBrb). (A)

P0293 -

StrateGems, No. 53, Jan-Mar 2011

14+13. PG 22½

[1nb4r/1p1pb2p/Bp2kn2/6qp/rP6/1P1PPK2/1P1B3P/RN1Q2NR]

Solution

1.f4 c5 2.f5 c4 3.f6 c3 4.fxe7 f5 5.g4 Kf7 6.e8B+ Ke6 7.Bh5 g6 8.g5 gxh5 9.g6 Qg5 10.g7 Sf6 11.g8S f4 12.Se7 f3 13.Sd5 Be7 14.Sb6 axb6 15.e3 Ra4 16.Ba6 f2+ 17.Ke2 f1B+ 18.Kf3 Bc4 19.d3 Bb3 20.cxb3 c2 21.Bd2 c1S 22.b4 Sb3 23.axb3

Proof game of the future with mixed Ceriani-Frolkin pieces (SBsb). (A)

P0294 -

StrateGems, No. 53, Jan-Mar 2011

14+13. PG 23½

[1nb2b1r/1p1p3p/Bp3n2/4k1qp/rP2P1Q1/BP2PK2/P3N2P/RNR5]

Solution

1.f4 c5 2.f5 c4 3.f6 c3 4.fxe7 f5 5.g4 Kf7 6.e8B+ Ke6 7.Bh5 g6 8.g5 gxh5 9.g6 Qg5 10.g7 Sf6 11.g8Q+ Ke5 12.Qb3 f4 13.Qb6 axb6 14.e4 Ra4 15.Qg4 f3 16.Ba6 f2+ 17.Ke2 f1B+ 18.Kf3 Bc4 19.b4 Bb3 20.cxb3 c2 21.Ba3 c1Q 22.Se2 Qc5 23.Rc1 Qce3+ 24.dxe3

Proof game of the future with mixed Ceriani-Frolkin pieces (QBqb). (A)

P0295 -

StrateGems, No. 53, Jan-Mar 2011

13+14. PG 23

[1n6/2kp2pp/Ppp2n2/p1r1pP2/2r4b/2P2PK1/1P1P1P1P/1NB2bNR]

Solution

1.c3 e5 2.Qb3 Be7 3.Qb6 axb6 4.g4 Ra4 5.Bh3 Rc4 6.a4 Bg5 7.a5 Qf6 8.a6 Kd8 9.Ra5 bxa5 10.Kf1 b6 11.Kg2 Bb7+ 12.Kg3 Bg2 13.Sa3 Qf3+ 14.exf3 f5 15.gxf5 Sf6 16.Bg4 Re8 17.Bh5 Re6 18.Bf7 Rec6 19.Bd5 R6c5 20.Be4 c6 21.Bd3 Kc7 22.Bf1 Bxf1 23.Sb1 Bh4#

P0296 -

StrateGems, No. 53, Jan-Mar 2011

7+16. PG 25

[r4n2/3ppp1p/1k1n1bpq/p1p5/1p6/5N2/8/RNBQKbrR]

Solution

1.c4 Sh6 2.c5 Sf5 3.c6 Sxc6 4.b4 Scd4 5.b5 c5 6.b6 Qxb6 7.h4 Kd8 8.h5 Kc7 9.h6 Qxh6 10.a4 b5 11.a5 b4 12.a6 Bxa6 13.e4 Bxf1 14.g4 a5 15.g5 Ra6 16.g6 Rxg6 17.f4 Kb6 18.Sf3 Rg1 19.e5 g6 20.e6 Sxe6 21.d4 Bg7 22.d5 Ra8 23.d6 Sxd6 24.f5 Sf8 25.f6 Bxf6.

All white pawns are captured on the 6th rank. Black pawns are not used for the captures. (A)

P0297 -

StrateGems, No. 53, Jan-Mar 2011

13+13. PG 30

[3qrn1r/1p1bn2k/2B1p3/b2pp1B1/3pP3/3K1P1N/2PNPP2/3QR2R]

Solution

1.h4 e5 2.h5 Qg5 3.h6 Qe3 4.dxe3 a5 5.Qd4 a4 6.Kd2 a3 7.Kd3 axb2 8.a4 Bb4 9.a5 Se7 10.a6 0-0 11.hxg7 c5 12.Rh6 cxd4 13.Re6 fxe6 14.a7 Rf3 15.gxf3 h5 16.Bh3 h4 17.Bf5 h3 18.Be4 h2 19.Bc6 h1R 20.e4 Rh8 21.Sh3 Kh7 22.g8R d5 23.Rg1 Sd7 24.Bg5 Sf8 25.Sd2 Bd7 26.Rae1 Re8 27.a8Q b1Q 28.Qa1 Ba5 29.Rh1 Qb6 30.Qd1 Qd8.

This is the 5th proof game showing 4 Pronkin promotions, and the first with 2 for each side. Moreover, the combination (QR) vs (qr) makes it a "proof game of the future". A (seemingly new) castling trick is used, so that the final Rh8 is a very economical Pronkin promotion. (A)

Cooked by Ryan McCracken: 1.h4 a5 2.h5 a4 3.h6 a3 4.d3 Ra4 5.Be3 Re4 6.dxe4 axb2 7.Qd4 e5 8.Kd2 d5 9.Kd3 Sd7 10.Sd2 b1R 11.a4 Rb6 12.a5 Bb4 13.a6 Se7 14.a7 0-0 15.hxg7 Rf6 16.Rh6 Rf3 17.gxf3 Re8 18.Bh3 Sf8 19.Bd7 c5 20.Re6 h5 21.Re1 h4 22.a8Q h3 23.Bc6 h2 24.Qaa1 h1R 25.Qd1 Rh8 26.Sh3 Kh7 27.g8R cxd4 28.Rgg1 Ba5 29.Rh1 Bd7 30.Bg5 fxe6.