Triangles, sort of

Today I put together this equation:

$eq=pow($i,4)*($x^$i+$y^$i+$i^$i)-pow(($x+$y+$i),$i);

It outputs some interesting patterns when I ran a series from -25 t0 25. The patterns change interestingly when $i>=1. Pretty cool and quite different from what I have found so far.

As soon as $i>1 we find Sierpiński's triangle (wow!)