% sierpinski2x2.tiles
% 2x2 proofreading construction from sierpinski.tiles
tile edges matches {{N E S W}*}
num tile types=21
num binding types=14
tile edges={
{1 0 0 1}[.1](red)
{10 0 1 2}[.5](magenta)
{1 0 10 8}[.5](magenta4)
{2 1 0 10}[.5](purple)
{8 10 0 1}[.5](purple4)
{9 11 11 9}(blue2)          % 0+0
{3 9 4 11} (blue3)
{4 3 3 4}  (slate grey)
{11 4 9 3} (blue4)
{9 14 14 9}(dark green)     % 1+1
{3 8 7 14} (green2)
{7 2 2 7}  (cyan)
{14 7 8 3} (green1)
{8 13 13 8}(gold4)          % 1+0
{2 9 6 13} (yellow2)
{6 3 2 6}  (ivory)
{13 6 8 2} (yellow1)
{8 12 12 8}(brown3)         % 0+1
{2 8 5 12} (tan2)
{5 2 3 5}  (gold)
{12 5 9 2} (tan1)
}
binding strengths=
{2 1 1 1 1 1 1 1 1 2 1 1 1 1}
% historical: aka sierproof2x2RSq.tiles