# prooftrees tree nodes on different line

While trying to write a tableaux proof tree with prooftrees, I had some difficulty with putting single and branching nodes on the same line.

\documentclass{article}
\usepackage{prooftrees}
\begin{document}

\begin{prooftree}
{
to prove=\neg(a \vee b) \vee ((a \vee b) \vee  b)
}
[{(a \vee b) \vee ((a \vee b) \vee  b)}, just = 1
[{\neg (a \vee b)} just = 2
[{a,b} just = 3
]
]
[{(a \vee b) \vee  b}
[{a \vee b}
]
[{b}
]
]
]
\end{prooftree}
\end{document}


I'd like to have 3. and 4. be on the same line, instead of different ones. how would I go about doing this? I'm writing with MiKTeX 2.9.6480 and TeXWorks, and typesetting with pdfLaTeX. (also there's no tag for prooftrees, which is odd)

• Welcome to TeX.se and thanks for posting a minimal document. I'm not quite sure what you want the tree to look like. But first thing is you're missing commas before the just commands. – Alan Munn Oct 9 '18 at 23:27
• The development version of prooftrees can do this at the cost of disabling all automatic moves. You just add not auto move to the tree's preamble. @AlanMunn However, it is not very well tested, although it has been used by one person for a book, so maybe it is OK. (Technically, it should be safer than the default, but it has had fewer eyes and fewer experiments.) – cfr Nov 11 '18 at 5:07