How to put a number inside the symbol as shown

I wanted to put the numbers or texts inside a mathematical symbol as shown in the picture. I am sorry, that I do not know the name of this particular mathematical symbol. Please guide me type the following notation in latex.

• Do you really need the whole image? Crop it keeping necessary portion only.
– topu
Dec 7 '21 at 5:24
• @mmr I need only the notation inscribing the number
– gete
Dec 7 '21 at 5:26
• What is it used for? @gete
– topu
Dec 7 '21 at 5:31
• In Horner's method of division algorithm of polynomial, we use thise notation to imply the remainder.
– gete
Dec 7 '21 at 5:33
• The polynom package supports typesetting polynomial long division using the Horner Schema. You should look into its manual to see the use. Dec 7 '21 at 5:36

As it seems not a conventional symbol, you can make a macro for using it. Like this:

\documentclass{article}

\newcommand{\horner}[1]{%
\begin{array}{@{\vline}l}\,#1\,\\\hline\end{array}
}

\begin{document}
Text

$\horner{866}$

Text
\end{document}


It is possible to use a closer symbol from steinmetz package.

\documentclass[a4paper,12pt]{article}
\usepackage{steinmetz}

\begin{document}
$\phase{866}$

\end{document}


or you can use esrelation package.

\documentclass[a4paper,12pt]{article}
\usepackage{esrelation}

\begin{document}
$\relationlifting{866}$

\end{document}