Please turn on javascript in your browser to play chess.
Posers and Puzzles

Posers and Puzzles

  1. Standard member wittywonka
    Chocolate Expert
    13 Feb '07 03:43
    How many possible moves (for white for ease sake) are there after:

    0 random half-moves: 20
    2 random half-moves:
    4 random half-moves:
    6 random half-moves:
    8 random half-moves:
    10 random half-moves:

    For example, I think there are a total of 20 opening moves for white...as for the rest, I am both too lazy and mathematically challenged to solve...

    Also...just a note...I have no idea to the answers, just curious...

    Also...another curiousity...is there any sort of pattern of increase in number of moves?
  2. 13 Feb '07 13:45 / 2 edits
    http://www.research.att.com/~njas/sequences/A048987
    http://www.research.att.com/~njas/sequences/A006494
    http://www.research.att.com/~njas/sequences/A019319
    http://www.research.att.com/~njas/sequences/A089957
    http://www.research.att.com/~njas/sequences/A090051
    http://www.research.att.com/~njas/sequences/A057745
    http://www.research.att.com/~njas/sequences/A083276
  3. Standard member XanthosNZ
    Cancerous Bus Crash
    13 Feb '07 14:27
    Originally posted by David113
    http://www.research.att.com/~njas/sequences/A048987
    http://www.research.att.com/~njas/sequences/A006494
    http://www.research.att.com/~njas/sequences/A019319
    http://www.research.att.com/~njas/sequences/A089957
    http://www.research.att.com/~njas/sequences/A090051
    http://www.research.att.com/~njas/sequences/A057745
    http://www.research.att.com/~njas/sequenc ...[text shortened]... n moves, including en passant and castling information, so why are the sequences not the same?)


    A position is different depending on whether en passant is possible. However, the above position is the same whether or not the last move was ...f4 as even if en passant were possible it couldn't be played due to the pin according to one sequence and two different positions according to the other.
  4. 14 Feb '07 02:27
    Originally posted by XanthosNZ
    [fen]rnbqkbnr/ppp3pp/8/3pPp2/5p2/8/PPPPQ1PP/RNB1KBNR w KQkq f6[/fen]

    A position is different depending on whether en passant is possible. However, the above position is the same whether or not the last move was ...f4 as even if en passant were possible it couldn't be played due to the pin according to one sequence and two different positions according to the other.
  5. 14 Feb '07 10:07
    Originally posted by XanthosNZ
    due to the pin
    what pin?
  6. Standard member XanthosNZ
    Cancerous Bus Crash
    14 Feb '07 21:49
    Originally posted by aging blitzer
    what pin?
    Hmmm is seems I messed up the example. Anyway, imagine the pawn that would take en passant is pinned to it's own king.
  7. Standard member HandyAndy
    Non sum qualis eram
    14 Feb '07 22:13
    Originally posted by XanthosNZ
    Hmmm is seems I messed up the example. Anyway, imagine the pawn that would take en passant is pinned to it's own king.
    its own king.