Constants such that
where is a real-valued smooth function on a region satisfying some boundary conditions.
Constants such that
where is a real-valued smooth function on a region satisfying some boundary conditions.
Weisstein, Eric W. "Wirtinger-Sobolev Isoperimetric Constants." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Wirtinger-SobolevIsoperimetricConstants.html