A decorative knot with 15 crossings and five-fold rotational symmetry (partly a variation on a design in George Bain's Celtic Art: The Methods of Construction, but changed from 6-fold symmetry to 5-fold symmetry and given rather different artistic rendering).
Self-made image, converted from a version of the following vector PostScript source code:

%!
306 396 translate .7 dup scale 18 rotate 1 setlinejoin 10 setlinewidth 1
setgray/y 2 def/z 4 def/w .85 def/q 2.87 def/r 2.87 def 0 3 12{72 mul/x
exch def gsave x rotate 0 -260 moveto 61.8033989 y mul -190.2113033 -260
sub y mul rlineto 200 288 cos mul 200 288 sin mul 93.2208255 48.4725757
139 arcn -8.5512512 14.7457109 z mul add -129.052939 16.963 z mul add
200 47.2746942 w mul sub 80.3444185 w mul neg 200 0 curveto 247.2746942
80.3444185 lineto 247.2746942 47.2746942 q mul add 80.3444185 80.3444185
q mul add -152.8241656 8.9792333 r mul add 210.3444185 92.787368 r mul
add -152.8241656 210.3444185 curveto gsave 24 setlinewidth 0 setgray
stroke grestore stroke grestore}for 1 setlinewidth .6 setgray 0 0 200 0
360 arc stroke 0 0 260 0 360 arc stroke 1 0 0 setrgbcolor 0 1 9{36 mul
90 add/x exch def 260 x cos mul 260 x sin mul 1.5 0 360 arc fill}for 0 1
9{36 mul 72 add/x exch def 200 x cos mul 200 x sin mul 1.5 0 360 arc
fill}for showpage
%EOF
AnonMoos