Which pentominoes have point symmetry

Coordinate Grids Links ». Leave a Reply Cancel reply Enter your comment here Fill in your details below or click an icon to log in:. Email required Address never made public. Name required. Follow Following. Sign me up. Already have a WordPress. Create a free Team What is Teams? Learn more. Are tiny point-symmetric grids of two Pentominos impossible to solve? Ask Question. Asked 1 year, 8 months ago.

Active 1 year, 8 months ago. Viewed 74 times. Filling such a board is, of course, trivial when using the same piece twice. Using the Y-piece twice on a point-symmetric hourglass board: O OOOO However, it seems impossible to do when using two different pieces. Improve this question. A good task for a computer program. Add a comment.

Active Oldest Votes. Therefore, the region in which one part is mapped onto the same part is: also point symmetric with the same center itself partitioned into two point symmetric regions with the same center and those two regions have the same area The smallest non-empty such region has an area of 4. Improve this answer. John Dvorak John Dvorak 2 2 silver badges 9 9 bronze badges. In the first part, do you make any assumptions if the point of rotation is on a cell, between two cells or between four cells?

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Using the area formula for a rectangle to derive other area formulas.