What is the fewest straight lines with which you can make exactly 100 squares?

For example with four vertical and five horizontal lines, evenly spaced, 20 squares are formed: twelve 1x1, six 2x2 and two 3x3.

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15 lines can create a 5x8 grid.

1x1 -- 40
2x2 -- 28
3x3 -- 18
4x4 -- 10
5x5 --   4
         ==
         100

Posted by Dej Mar on 2006-04-30 17:25:24