Perfect Parallelepiped
A perfect parallelepiped is a parallelepiped with integer-length edges, face diagonals, and body diagonals, but not necessarily with all right angles; a perfect cuboid is a special case of a perfect parallelepiped. In 2009, a perfect parallelepiped was shown to exist, answering an open question of Richard Guy. Solutions with only a single oblique angle have been found.
Read more about this topic: Euler Brick
Famous quotes containing the word perfect:
“There is no such thing as a perfect leader either in the past or present, in China or elsewhere. If there is one, he is only pretending, like a pig inserting scallions into its nose in an effort to look like an elephant.”
—Liu Shao-Ch’I (b. 1898)