Re: Re: Re: Re: Combinatorica questions!!!
- To: mathgroup at smc.vnet.net
- Subject: [mg20797] Re: [mg20777] Re: [mg20733] Re: [mg20645] Re: [mg20499] Combinatorica questions!!!
- From: "Arnold Knopfmacher" <arnoldk at cam.wits.ac.za>
- Date: Sun, 14 Nov 1999 18:13:48 -0500 (EST)
- Organization: MS, University of the Witwatersrand
- Sender: owner-wri-mathgroup at wolfram.com
Perhaps more interesting is to consider the number of paths that other chess pieces can use to cross an n-by-n chessboard from position {0,0} to {n-1,n-1}. As with the rook we dont allow moves that decrease either coordinates at any step. On an 8-by-8 board, I get for a queen (or king) 48639 paths. For a bishop there is only one path (down the diagonal) and no ways for a knight. For the bishop or knight, the problem becomes much more interesting if we allow moves in positive or negative directions with the proviso that the piece cant return to any square its already occupied ( or go off the board). This avoids possible infinite loops of moves. For example for a 3-by-3 board there are 2 paths for a knight. I dont know the answers under these conditions for a standard 8-by-8 board. Arnold Knopfmacher Dept of Computational and Applied Maths Witwatersrand University Johannesburg 2050 South Africa http://www.wits.ac.za/science/number_theory/arnold.htm Fax: 2711-4039317 Phone: 2711- 7163353 email: arnoldk at gauss.cam.wits.ac.za