A right-angled parallelepiped with dimensions , where , , and are integers.
Harmonic Brick
See also
Brick, de Bruijn's Theorem, Euler BrickExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Harmonic Brick." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/HarmonicBrick.html