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Posers and Puzzles

Posers and Puzzles

  1. 05 Jun '08 20:21 / 1 edit
    Edit 1: Forgot Title (dope) Bishop on e4 or e5.

    Look at this position.



    The game has been played as per normal chess
    but with one additional rule.

    Pieces and pawns can never move to a square of the
    opposite colour from the one they start on:

    so bishops are unaffected.
    Knights cannot move at all!
    0-0 is legal but 0-0-0 is not etc.

    There is also a White Bishop on the board.

    Given the above conditions you have to decide is the
    White Bishop on e4 or e5.

    Don't guess - need an explanation.

    (sorry if this one has been posted before. It's a classic.)
  2. 05 Jun '08 21:03 / 2 edits
    E5. pieces on black squares must be taken by pieces on black squares. But in the position, no pieces on black squares could have moved. Thus, E5.

    edit: think about "what was the last black piece to be taken taken by?"

    Reminds me of a puzzle I made a while back, that understandably isn't a classic

    The game has been played like normal chess, but with the added stipulation that pieces cannot move backwards or sideways. They must always advance. (ie a white bishop can go from A3 to C5 but not back again. A pawn can promote but then is paralyzed.)
    In the position, one of the black pieces has been left out.

    Who has won the game?
  3. 05 Jun '08 21:56 / 1 edit
    The correct answer.

    My one took me a while because I figured as the White King
    never moved so the Black King had not moved. (doh).

    So spent a ages trying to work out what took last white
    piece - then saw Kf7xe8 was legal.

    Looking at yours now.
  4. Standard member SwissGambit
    Caninus Interruptus
    06 Jun '08 00:30
    Originally posted by doodinthemood
    E5. pieces on black squares must be taken by pieces on black squares. But in the position, no pieces on black squares could have moved. Thus, E5.

    edit: think about "what was the last black piece to be taken taken by?"

    Reminds me of a puzzle I made a while back, that understandably isn't a classic
    [fen]4k3/7P/8/4n3/4n3/8/4P1P1/4K3 w[/fen]
    The ...[text shortened]... lyzed.)
    In the position, one of the black pieces has been left out.

    Who has won the game?
    If there is a Black piece missing, it must be on f1 [someone captured a wB there]. Has to be Q [who else can get there?]. I'm not quite sure how anyone wins though - I would think White would just play e3 ASAP and advance the K as far up the board as he can.
  5. 06 Jun '08 02:06 / 1 edit
    Yes SG is correct - must have been the Queen that took on f1.

    Two Knights in diagram to show it was not a Knight.
    Pawn on h7 to show last legal move by White.
    So Qxf1 is mate.

    Moot point without trying to find fault or sound clever.

    As the Queen can only move forward and therefore cannot
    take sideways - is the King really in danger of being taken
    on the next move?

    But there again not all chess pieces in the 'normal game '
    attack the same way as they move (pawns).
    So one can argue it's OK.

    Having said all that - I may of course be wrong.
    (it has been known to happen).

    PS. A friend of mine says on uchess.com their site does not
    recognise en passant in their blitz games. I was thinking of
    going there to see if this is so.

    (Can you think of any mainline opening theory that features e.p.?)

    Also how will I know that my opponent has tried to play e.p in
    a game and not been allowed to do it?

    So construct a game where e.p is the only way out of mate.
    (there was long game on this site a few weeks ago where
    the players missed e.p. as the only move).

    What is the quickest way to show e.p. only move from the start position?
  6. Standard member SwissGambit
    Caninus Interruptus
    06 Jun '08 06:02 / 2 edits
    Originally posted by greenpawn34
    Yes SG is correct - must have been the Queen that took on f1.

    Two Knights in diagram to show it was not a Knight.
    Pawn on h7 to show last legal move by White.
    So Qxf1 is mate.

    Moot point without trying to find fault or sound clever.

    As the Queen can only move forward and therefore cannot
    take sideways - is the King really in danger of being t s the only move).

    What is the quickest way to show e.p. only move from the start position?
    But Qxf1 is not mate - the Queen cannot move sideways!

    If a pawn is paralyzed upon promotion, then why should a regular piece be any different when it hits the last rank?

    Edit: And a pawn only gives check on the same squares as it captures. Hence, if there is no threat of capture on square X, there is no check given to square X either.
  7. Standard member SwissGambit
    Caninus Interruptus
    06 Jun '08 06:08
    Originally posted by greenpawn34
    What is the quickest way to show e.p. only move from the start position?
    1. d4 f5 2. d5 Kf7 3. Qd4 Kg6 4. Qxg7+ Kh5 5. h4 f4 6. g4+



    6...fxg3
  8. 06 Jun '08 06:45
    For mainline opening theory with EP, try the petrof:
    e4 e5
    nf3 nf6
    d4 ed
    e5 ne4
    qxd4 d5

    and EP is common.
  9. 06 Jun '08 14:14 / 2 edits
    So my answer is wrong - or is it? Is it?

    That en passant example from Swiss Gambit is most likely the
    quickest but I'm going it open it to the Corner and see
    is anybody finds a dual.

    http://chessedinburgh.co.uk/chandler.php

    Will post late tonight.

    Of course the Petroff - It was really a question to myself.
    I actually played the above line as Black v an IM about a year ago.
    I knew something was nipping my brain when I put the question.
    ( I lost - I played him in 1978 and won - he waited 29 years for revenge!).

    So I'll hit that uchess site and play Petroff's to test the theory.

    Possible a whole new genre of chess problems waiting to
    be discovered if you state in condition - 'faulty program.'

    The computer does not recognise Knight checks.

    If you take a piece and then move the capturing piece.
    Then the piece that was taken reappears on the vacant square.

    eg 1.Qd1xBd4 2.Qe4 and the Black Bishop pops back on d4.
    (the computer has not cleared it from it's memory bank).

    I suppose the conditions are endless.

    I'll see if I can come up with one.

    Cheers.
  10. Standard member SwissGambit
    Caninus Interruptus
    06 Jun '08 16:43
    Originally posted by greenpawn34
    That en passant example from Swiss Gambit is most likely the
    quickest but I'm going it open it to the Corner and see
    is anybody finds a dual.
    Obviously, there are duals...for example, White could start 1.h4 2.c3 3.Qb3 4.Qe6 - the Q is just as effective there as on g7. This line even saves a move for White [not that it matters - he has to wait for Black anyhow].
  11. 06 Jun '08 16:55 / 1 edit


    White to play and mate in 3. When pieces capture pieces, then move away, the captured piece re-appears in the vacant square as the computer hasn't cleared it from it's memory bank. None of the pieces on the board has captured something on the square it's on.

    (I'm aware of the illegality of the position.)
  12. 06 Jun '08 17:04
    Originally posted by doodinthemood
    [fen]5n1k/8/8/7K/8/3Q4/2R6/8[/fen]

    White to play and mate in 3. When pieces capture pieces, then move away, the captured piece re-appears in the vacant square as the computer hasn't cleared it from it's memory bank. None of the pieces on the board has captured something on the square it's on.

    (I'm aware of the illegality of the position.)
    Is the solution unique?
  13. 06 Jun '08 17:10
    I think so, but it's made by me, and I'm not very good at getting unique solution puzzles.
  14. 06 Jun '08 19:36 / 1 edit
    edit: sorry guys. I fritzd the position to check if it had any normal mates in 3, and it told me it didn't, but it turns out there are normal mates in three. I will carry on working on the concept and will hopefully get back to you with a better version.

    edit: ok, same stip as before, only I'm fairly sure it works now:


    Stupid fritz, alledgedly perfect.
  15. 06 Jun '08 22:05
    What you want is a position where you have to work out what
    piece is 'hidden' under the piece about to move.
    (not simple position just out the opening).

    Working on latest article ATM. Am going to ask for EP games
    (see above) reckon SG's will not be bettered.

    What about the answer to your original question?