Abstract
In this paper for any $\varepsilon >0$ we construct a new proper $k$-ball-contractive retraction of the closed unit ball of the Banach space $C^m [0,1]$ onto its boundary with $k < 1+ \varepsilon$, so that the Wośko constant $W_\gamma (C^m [0,1])$ is equal to $1$.
Citation
Diana Caponetti. Alessandro Trombetta. Giulio Trombetta. "Optimal retraction problem for proper $k$-ball-contractive mappings in $C^{m} [0,1]$." Topol. Methods Nonlinear Anal. 53 (1) 111 - 125, 2019. https://doi.org/10.12775/TMNA.2018.041