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# Tag Archives: rectangles

## Picture this

Picture this! is a very cool interactive thingy, made by Jason Davies, intended to get students (or anyone, really) thinking about some interesting math. Go play around with it and see if you can answer any of the listed questions … Continue reading

Posted in challenges, links, pattern, pictures
Tagged interactive, picture, rectangles, this
6 Comments

## 17×17 4-coloring with no monochromatic rectangles

Quick, what’s special about the following picture? As just announced by Bill Gasarch, this is a grid which has been four-colored (that is, each point in the grid has been assigned one of four colors) in such a way that … Continue reading

Posted in open problems, pattern, people, pictures
Tagged 17x17, four-coloring, graph, grid, monochromatic, rectangles
5 Comments

## Chessboard counting: solutions and further challenges

And now for some solutions to the chessboard counting challenges. The first challenge was to count the number of squares of any size on an 8×8 chessboard. The key here (as with many counting problems) is to break the problem … Continue reading

Posted in challenges, counting, solutions
Tagged chess, chess board, counting, rectangles, squares
2 Comments

## Chessboard counting

I am currently doing a unit on combinatorics (the mathematical study of counting) with my precalculus students, and I was inspired to post a few counting-themed challenge problems for your enjoyment. (Also, it’s my spring break!) As you probably know, … Continue reading