The homotopy dimension of codiscrete subsets of the 2-sphere S2
J. W. Cannon, Gregory R. Conner · Fundamenta Mathematicae · 2007
Andreas Zastrow conjectured, and Cannon–Conner–Zastrow proved, that filling one hole in the Sierpiński curve with a disk results in a planar Peano continuum that is not homotopy equivalent to a 1-dimensional set. Zastrow's example is the moti