在上图中，请注意中心和第3环未填充。

In the illustration above, notice that the center and 3rd ring are not filled.

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在上图中你可以看到从一个最初的平面获得一片叶子。

Above you can see the leaf obtained from the initial plane.

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在上图中你可以看到从一个最初的平面获得一片叶子。

Above you can see the leaf obtained from the initial plane.

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