I'm trying to typeset some homework that deals with set theory and in particular I'm trying to write the "model-theoretic" notion of forcing. I put model-theoretic in quotes because I don't know the proper name for it. There's the forcing relation given by
$\Vdash$ (i.e. it looks like similar to
||-), and I'm looking for the relation that looks like
||=, i.e. kind of like the
$\models$ symbol or
$\vDash$ but with an extra vertical line.
The strange thing is that it looks like the AMS packages have
$\nVDash$ (i.e. the negation of the symbol I'm looking for) available, but not
$\VDash$. Detexify doesn't seem to be helping me here. Are there any symbols which look like the hypothetical
$\VDash$ I'm looking for (hopefully within
amssymb, as I usually like to cut down on the number of packages I need to install to maintain portability across machines)?