Somewhat symmetric representation of "8_4" knot of mathematical knot theory, made from circular arcs and 45° straight lines.
AnonMoos
<p>Generated from the following vector PostScript source code: 
</p>
<pre>%!
306 496 translate .4 dup scale 32 setlinewidth .92 .96 1 setrgbcolor
1 setlinejoin/z{20000 sqrt}def/y{gsave 60 setlinewidth 0 setgray}def
z 2 mul z -2 mul 100 315 45 arc 0 0 100 45 135 arc
z -2 mul z -2 mul 100 135 225 arc z z -5 mul 100 225 45 arc
z -2 mul 0 100 225 45 arcn 0 z neg lineto
z 2 mul 0 100 135 315 arcn z neg z -5 mul 100 135 315  arc
closepath y stroke grestore stroke 0 setlinejoin
y 16 z add 16 moveto -32 -32 rlineto stroke
16 z sub 16 moveto -32 -32 rlineto stroke
16 16 z 3 mul sub moveto -32 -32 rlineto stroke
16 16 z 5 mul sub moveto -32 -32 rlineto stroke
-16 z 2 mul add 16 z sub moveto 32 -32 rlineto stroke
-16 z 2 mul sub 16 z sub moveto 32 -32 rlineto stroke
-16 z add 16 z 4 mul sub moveto 32 -32 rlineto stroke
-16 z sub 16 z 4 mul sub moveto 32 -32 rlineto stroke
grestore 18 z add 18 moveto -36 -36 rlineto stroke
18 z sub 18 moveto -36 -36 rlineto stroke
18 18 z 3 mul sub moveto -36 -36 rlineto stroke
18 18 z 5 mul sub moveto -36 -36 rlineto stroke
-18 z 2 mul add 18 z sub moveto 36 -36 rlineto stroke
-18 z 2 mul sub 18 z sub moveto 36 -36 rlineto stroke
-18 z add 18 z 4 mul sub moveto 36 -36 rlineto stroke
-18 z sub 18 z 4 mul sub moveto 36 -36 rlineto stroke showpage
%EOF</pre>