Blaschke's theorem

Blaschke's theorem

[′bläsh·kəz ‚thir·əm]
(mathematics)
The theorem that a bounded closed convex plane set of width 1 contains a circle of radius 1/3.
References in periodicals archive ?
Blaschke's Theorem is an extension of the classical Heine-Borel Theorem which states that every closed and bounded subset K [??] [R.sup.n] is sequentially compact.
In 1986, De Blasi and Myjak ([4]) introduced the concept of weak sequential convergence on the hyperspace WCC (X): Suppose [A.sub.n]; A [member of] WCC (X); they define [A.sub.n] converges to [A.sub.0] weakly ([mathematical expression not reproducible]) if and only if [mathematical expression not reproducible] (x*) [right arrow] [mathematical expression not reproducible] (x*) = sup{x* (a) | a [member of] [A.sub.0]} and proved an infinite dimensional version of Blaschke's Theorem and other results.