In TeXForm#
TeXForm parses this entry as a character leaf mapped to U+25B3 (WHITE UP-POINTING TRIANGLE).
See also#
\backslashbase\lnotbase\negbase
The △ symbol (White up-pointing triangle, U+25B3), written as \triangle in LaTeX math mode.
TeXForm parses this entry as a character leaf mapped to U+25B3 (WHITE UP-POINTING TRIANGLE).
\backslash base\lnot base\neg base