I'm trying to create a symbol of a gray triangle with a black border. I managed to do so using:
However, the two triangles go out of sync when the
\factor is used in a subscript or superscript. That is, the space becomes too large and the black triangle is no longer over the gray one.
Is there a way to ask the space to be relative to the current font, such that it will take into account whether it is in super/sub-script?