For n=3,4,5,6,7,8 find:
a) The minimum number of counters that need be placed on a nxn chessboard such that no additional counters can be placed without creating any straight line of 3;
b) The maximum number of counters that can be placed on a nxn chessboard such that no three lie in a straight line.
Remember that positions like A1, B3, and C5 are in a straight line.
(Try to continue the sequences if you can)
(In reply to
re: Minimum and Maximum by Jer)
Hmm...I can't speak for Dej Mar, but I read that note at the end of the problem, and yet I didn't realize what it was saying. For some reason when I read it I was picturing something like A1, C3, E5 (i.e. along a diagonal). Good catch!
If it's true that you cannot have three in any straight line, like the one you pointed out, then I've been going about this all wrong! :)

Posted by tomarken
on 20060427 14:13:28 