Ehrenstein Illusion

Author

Eric W. Weisstein
June 6, 2002

This notebook downloaded from http://mathworld.wolfram.com/notebooks/RecreationalMath/EhrensteinIllusion.nb.

For more information, see Eric's MathWorld entry http://mathworld.wolfram.com/EhrensteinIllusion.html.

©2005 Wolfram Research, Inc. except for portions noted otherwise

Initialization

EhrensteinIllusion[{r_,n_},a_]:=Module[{},
Graphics[{
Table[Circle[{0,0},r+(1-r)i/(n-1)],{i,0,n-1}],
Thickness[.015],
Line@Table[a{Cos[#],Sin[#]}&[2Pi i/4],{i,0,4}]
}]
]

Figure

Show[EhrensteinIllusion[{.3,20},.8],AspectRatio->Automatic]