Friday, April 18, 2008

Pawns Albinos and Pickaninnies (1)

 Theme Albino : A white pawn makes from its starting square four different moves (one step forward, two steps forward, capture left, capture right).

 Theme Pickaninny : A black pawn makes from its starting square four different moves (one step forward, two steps forward, capture left, capture right).

 (Problem 41) A. C. Reeves, ”Probleemblad”, 1965 White plays and mates in 2 moves #2 (9+10) [1s1b1B2/1Q2p3/1p1S1Rp1/S1k5/p3R3/Kp1p4/1sP5/5B2]

In problem-41 there are several tries: {1.Qd5+? Kxd5!}, {1.Qc6+? Sxc6!}, {1.Rf5+? gxf5!}, {1.Sxb3+? axb3!}, {1.Rxa4? exd6!}, {1.Rc4+? Sxc4+!}, {1.Re5+? Kd4!}, but we specifically note that four tries Albino are answered with four defenses Pickaninny:
Try: {1.c3? [2.Re5#] exf6!}
Try: {1.c4? [2.Qd5#] e6!}
Try: {1.cxb3? [2.b4#] exd6!}
Try: {1.cxd3? [2.d4#] e5!}
Key: 1.Rb4! [2.Se4#]
1...Sc4 2.Rxc4#
1...exd6 2.Bxd6#

In problem-42 black tries to defend with Pickaninny, but white has four continuations with Nowotny intersections.

 (Problem 42) N. Littlewood, First Prize, ”B.C.P.S. Ring Tourney”, 1966 White plays and mates in 3 moves #3 (12+11) [bb2RSs1/r4p2/qr4PP/p1P1B1k1/3S4/2sP1RpQ/5PK1/8]

There are several tries: {1.Sh7+? Kxg6!}, {1.Bxg3? Bxg3!}, {1.Bf4+? Bxf4!}, {1.Bxb8? Sxh6!}, {1.Qf5+? Kxh6!}, {1.Qg4+? Kxg4!}, {1.Qxg3+? Kh5!}, {1.Qh5+? Kxh5!}, {1.Qh4+? Kxh4!}, {1.fxg3? Rb2+!}.
Key: 1.Re6! ( > 2 Sh7#)
1...f6 2.Rd6 (Nowotny on d6) Rxd6 / Bxd6 3.Bf4# / Sde6#
1...f5 2.Rc6 (Nowotny on c6) Rxc6 / Bxc6 3.Rxg3# / Sde6#
1...fxe6 2.c6 (Nowotny on c6) Rxc6 / Bxc6 3.Rxg3# / Sde6#
1...fxg6 2.Bc7 (Nowotny on c7) Rxc7 / Bxc7 3.Re5# / Sh7#

In problem-43 we see that the mates for Pickaninny are changed in two phases.

 (Problem 43) A. C. Reeves, ”Die Schwalbe”, 1965 (Set play). White plays and mates in 2 moves * #2 (13+6) [R2Sr3/RB1pk1P1/PpP1P1P1/1K2p1P1/3Q4/2Sr4/8/8]

First Phase: (*) (Set play)
1...d6 / d5 / dxc6+ / dxe6
2.Sd5# / Qb4# / Bxc6# / Bc8#

If we start with checks, we do not achieve our goal:
Tries: {1.Qb4+? d6!}, {1.Qxd7+? Rxd7!}, {1.Sd5+? Kd6!}

Last Phase: Key: 1.Qxe5!
1...d6 / d5 / dxc6+ / dxe6
2.Qf6# / Qc7# / Sxc6# / Qxe6# (four mates are changed).

In the problem-44 the King Kf6 with the Bishop Bg7 form a royal battery which fires with a move of Kf6.

 (Problem 44) Henry D’ Oyly Bernard, Second Prize ex aequo, ”Good Companions”, 1917 (Set play). White plays and mates in 2 moves * #2 (14+10) [2s3b1/6B1/p3PKP1/p1pp1R2/QbPk1pr1/4sP2/1PPS1P2/3R4]

First Phase: (*) (set play)
1...Bb~ (makes a random move) / Bxd2 2.Sb3# / Rxd2#

There are many tries : {1.Bh8? Rh4!}, {1.Rxf4+? Rxf4+!}, {1.Rxd5+? Sxd5+!}, {1.Qb3? dxc4!}, {1.Qb5? axb5!}, {1.Qa3? Bxa3!}, {1.Qxb4? cxb4!}, {1.fxg4? Sxg4+!}, {1.fxe3+? Kxe3!}, {1.Sb1+? Sxd1!}, {1.Se4+? Sxd1!}, {1.Sb3+? Kxc4!}, {1.c3+? Kd3!}.

Last Phase: Key: 1.Qa1!
The key brings black in zugzwang situation, despite the fact that black has many available moves. The four moves of Bb4 are handled by the Albino b2.
1...Ba3 / Bxd2 / Bc3 / Bxa5
2.bxa3# / b3# / bxc3# / b4#

[This post in Greek language].