[Tex/LaTex] How to write the L-shaped symbol in latex

symbols

I want to write the following equation in latex but dunno what's that L-shaped symbol.
enter image description here

I tried "\llcorner", but this is not what I exactly want… It looks like the following image:
enter image description here

I also tried Mathpix and read the great, big list of latex symbols, but couldn't find it. So, any help is definitely appreciated.

Best Answer

It could be built from \rules.

\documentclass{article}
\usepackage{mathtools}
\usepackage[scr=boondoxupr]{mathalpha}
\newcommand*{\Lcorner}{%
    \mathchoice%
        {\mathrel{\makebox[7pt][c]{\rule{.4pt}{7.5pt}\rule{5pt}{.4pt}}}}%
        {\mathrel{\makebox[7pt][c]{\rule{.4pt}{7.5pt}\rule{5pt}{.4pt}}}}%
        {\mathrel{\makebox[5.5pt][c]{\rule{.4pt}{5.25pt}\rule{3.5pt}{.4pt}}}}%
        {\mathrel{\makebox[4pt][c]{\rule{.4pt}{3.75pt}\rule{2.5pt}{.4pt}}}}%
}
\DeclareMathOperator{\Tan}{Tan}

\begin{document}
\(\displaystyle \Lcorner\)
\(\textstyle \Lcorner\)
\(\scriptstyle \Lcorner\)
\(\scriptscriptstyle \Lcorner\)

\(\displaystyle \Tan^k( \mathscr{H}^k \Lcorner F(E), y ) = DF(x)[\Tan^k( \mathscr{H}^k \Lcorner E, x)]\)

\(\textstyle \Tan^k( \mathscr{H}^k \Lcorner F(E), y ) = DF(x)[\Tan^k( \mathscr{H}^k \Lcorner E, x)]\)

\(\scriptstyle \Tan^k( \mathscr{H}^k \Lcorner F(E), y ) = DF(x)[\Tan^k( \mathscr{H}^k \Lcorner E, x)]\)

\(\scriptscriptstyle \Tan^k( \mathscr{H}^k \Lcorner F(E), y ) = DF(x)[\Tan^k( \mathscr{H}^k \Lcorner E, x)]\)
\end{document}
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