Posers and Puzzles

Posers and Puzzles

  1. SubscriberBigDoggProblem
    Court Jester
    lacking discretion
    Joined
    26 Nov '04
    Moves
    124059
    18 Jun '05 00:49

    Is the position legal?
  2. Standard memberabejnood
    Independant Thinker
    Young World
    Joined
    01 Jul '04
    Moves
    19393
    18 Jun '05 01:46
    Originally posted by BigDoggProblem
    [fen]8/5N2/2kP1r2/7b/P7/6KB/7r/2R3BQ[/fen]
    Is the position legal?
    of course its not, why would you ask if it was?
    can't have double check with the queen and rook, also, if the queen was to check, it can't have moved, which means that the rook was blocking it, meaning that BLACK moved his rook out of the way, leaving the queen checking, an illegal move.
  3. SubscriberBigDoggProblem
    Court Jester
    lacking discretion
    Joined
    26 Nov '04
    Moves
    124059
    18 Jun '05 03:28
    Originally posted by abejnood
    of course its not, why would you ask if it was?
    can't have double check with the queen and rook, also, if the queen was to check, it can't have moved, which means that the rook was blocking it, meaning that BLACK moved his rook out of the way, leaving the queen checking, an illegal move.
    Why is there a pawn on a4?
  4. Standard memberskeeter
    515 + 30 days
    Account suspended
    Joined
    08 Mar '03
    Moves
    38202
    18 Jun '05 04:201 edit
    Originally posted by BigDoggProblem
    [fen]8/5N2/2kP1r2/7b/P7/6KB/7r/2R3BQ[/fen]
    Is the position legal?
    Oh yes it is.



    .......Rf6+
    Kg3. d5
    c5d6xd5 (en passant) and we are there.

    skeeter
  5. Standard memberskeeter
    515 + 30 days
    Account suspended
    Joined
    08 Mar '03
    Moves
    38202
    18 Jun '05 04:331 edit
    Nope. Forgot about the bishop check, but anyway, it's white's en passant capture that permits the rook / queen double check.

    skeeter
  6. Joined
    30 Oct '04
    Moves
    7797
    18 Jun '05 07:16
    Originally posted by BigDoggProblem
    Why is there a pawn on a4?
    And why is there a knight at f7?
  7. Standard memberjfkjmh
    nice one
    bed, chair or floor
    Joined
    03 Oct '04
    Moves
    4854
    18 Jun '05 08:53
    Originally posted by ilywrin
    And why is there a knight at f7?
    Pawn on a4 and knight f7 are helpful for a checkmate.
  8. Standard memberskeeter
    515 + 30 days
    Account suspended
    Joined
    08 Mar '03
    Moves
    38202
    18 Jun '05 09:32
    Originally posted by jfkjmh
    Pawn on a4 and knight f7 are helpful for a checkmate.
    What?? The question is "can the displayed position be reached legally" - not, who can be mated. Jesus wept.

    skeeter
  9. Joined
    30 Oct '04
    Moves
    7797
    18 Jun '05 09:351 edit
    Okay, then the position is perfectly legal (only you have to assume two en passants happened)
    Let's see if I can get the Fen right from the first try:


    So the last moves were 1.g4 fxg++ 2.Kxg3+ d5 3.cxd#
    EDIT: sorry didn't get the fen right from the first time 🙁
  10. SubscriberBigDoggProblem
    Court Jester
    lacking discretion
    Joined
    26 Nov '04
    Moves
    124059
    18 Jun '05 19:321 edit
    Originally posted by ilywrin
    Okay, then the position is perfectly legal (only you have to assume two en passants happened)
    Let's see if I can get the Fen right from the first try:
    [fen]8/3p1N2/2k2r2/2P4b/P4p2/5K1B/6Pr/2R3BQ w - - 0 1 [/fen]

    So the last moves wer ...[text shortened]... cxd#
    EDIT: sorry didn't get the fen right from the first time 🙁
    That's right, ilywrin. Two ep captures must have occurred for the position to be legal. The problem was composed by Pal Benko and appeared in StrateGems in 1999.

    Pa4 and Nf7 appear to be only needed for the finale to be mate. (An 'artistic touch' from the author, but not relevant to the solution). I'd prefer the problem with less material on the board instead.


    Same solution.
  11. Joined
    30 Oct '04
    Moves
    7797
    18 Jun '05 20:14
    Originally posted by BigDoggProblem
    That's right, ilywrin. Two ep captures must have occurred for the position to be legal. The problem was composed by Pal Benko and appeared in StrateGems in 1999.

    Pa4 and Nf7 appear to be only needed for the finale to be mate. (An 'artistic touch' from the author, but not relevant to the solution). I'd prefer the problem with less material on the board instead.

    [fen]8/8/2kP1r2/7b/8/6KP/7r/2R4B[/fen]
    Same solution.
    This is illegal however since the bishop at h1 cannot get there if there is/was a white pawn at g2.
  12. SubscriberBigDoggProblem
    Court Jester
    lacking discretion
    Joined
    26 Nov '04
    Moves
    124059
    18 Jun '05 21:312 edits
    Originally posted by ilywrin
    This is illegal however since the bishop at h1 cannot get there if there is/was a white pawn at g2.
    D'oh! Unfortunately, this means I'm stuck with something like...


    I have to use Ng2 because after -1.axb6ep+ b7-b5 -2.Kd3xPe3+ dxe3ep+ -3.e2-e4, a Pg2 would make the position illegal again (Rf2 no exit!).
  13. Joined
    30 Oct '04
    Moves
    7797
    19 Jun '05 06:461 edit
    Originally posted by BigDoggProblem
    D'oh! Unfortunately, this means I'm stuck with something like...
    [fen]8/8/kP1r4/5b2/8/4KP2/5rN1/R4B2 b - - 0 3[/fen]

    I have to use Ng2 because after -1.axb6ep+ b7-b5 -2.Kd3xPe3+ dxe3ep+ -3.e2-e4, a Pg2 would make the position illegal again (Rf2 no exit!).
    And you need a White piece at g2, why exactly?
    EDIT: Nevermind just saw it 😉

Back to Top