literate-programmingsymbols
Usually, the list concatenation operator in Haskell is printed as overlapping double plus signs in books.
(In ASCII it is just ++)
How can I typeset this sign in Haskell (in and perhaps outside of math mode)?
What are other Haskell operators which could be typeset more beautiful in LaTeX?
It seems like you might be after so-called "vulgar fractions". One such package that provides this is xfrac by means of \sfrac{<num>}{<denom>}. A similar functionality is provided by nicefrac that supplies an analogous \nicefrac{<num>}{<denom>}. With package options one is also able to choose between "ugly" and "nice" (default) fractions. And finally there's faktor that produces similar-style fractions using \faktor{<num>}{<denom>} (it requires the amssymb package though). Here are some comparisons:
\documentclass{article}
\usepackage{xfrac}% http://ctan.org/pkg/xfrac
\usepackage{nicefrac}% http://ctan.org/pkg/nicefrac
\usepackage{faktor}% http://ctan.org/pkg/faktor
\usepackage{amssymb}% http://ctan.org/pkg/amssymb
\usepackage{lmodern}% http://ctan.org/pkg/lmodern
\begin{document}
\renewcommand{\arraystretch}{1.5}
\begin{tabular}{lll}
\verb!\xfrac! & $\sfrac{\mathbf{v}}{x}$ & $\sfrac{\mathbf{v}_1,\mathbf{v}_2}{x_1,x_2}$ \\
\verb!\nicefrac! & $\nicefrac{\mathbf{v}}{x}$ & $\nicefrac{\mathbf{v}_1,\mathbf{v}_2}{x_1,x_2}$ \\
\verb!\faktor! & $\faktor{\mathbf{v}}{x}$ & $\faktor{\mathbf{v}_1,\mathbf{v}_2}{x_1,x_2}$
\end{tabular}
\end{document}
The choice of lmodern was because of minor font substitutions when it comes to typesetting the denominator & numerator. It is also possible to write a macro that would typeset these respective entries differently, if needed. My choice of \mathbf{...} for the numerator was just a style choice.
Usually \mid is used for the "is a divisor of" relation. It's just a vertical bar, but declared a relation symbol.
For the negation, \nmid from amssymb is better than \not\mid that doesn't give a good result.
It is surely a good defining semantically sound names, for instance
\usepackage{amssymb}
\newcommand{\divides}{\mid}
\newcommand{\notdivides}{\nmid}
Best Answer
I couldn’t find the symbol in
symbols, but it is easy enough to define:This produces
If you use
xelatexorlualatexwithunicode-math, you can just write ⧺ (U+29FA DOUBLE PLUS) or its alias \doubleplus. This gives (with XITS fonts)