# LaTeX Tree Diagram

I'm trying to recreate the diagram on this website: http://www.njohnston.ca/2013/04/the-minimal-superpermutation-problem/ and am finding difficulty with joining all the nodes in the third row to a singular node. This is what I have got so far:

\begin{center}
\begin{tikzpicture}[sibling distance=5em,
every node/.style = {shape=circle,
draw, align=center,}]]
\node {$123121321$}
child { node {123}
child {node {1234123} } }
child { node {231}
child {node {2314231} } }
child {node {312}
child {node {3124312} } }
child {node {213}
child {node {2134213} } }
child {node {132}
child {node {1324132} } }
child {node {321}
child {node {3214321} } };
\end{tikzpicture}
\end{center}

• Welcome to TeX.se. Please don't post code fragments, but instead put your fragment into a complete compilable document. – Alan Munn Apr 8 at 20:21

I'd use forest. The \foreach loop at the end can be used for your original code, too (after changing the node names).

\documentclass[border=3.14mm]{standalone}
\usepackage[edges]{forest}
\usetikzlibrary{shapes.geometric}
\begin{document}

\begin{forest}
for tree={draw, ellipse,edge={-latex}}
[123121,alias=top
[123
[1234123,alias=n-1]
]
[231
[2314231,alias=n-2]
]
[312
[3124312,alias=n-3]
]
[213
[2134213,alias=n-4]
]
[132
[1324132,alias=n-5]
]
[321
[3214321,alias=n-6]
]
]
\node[ellipse,draw] (Pft) at ([yshift=-pi*1.1cm]top) {1234\dots};
\foreach \X in {1,...,6}
{\draw[-latex] (n-\X) -- (Pft);}
\end{forest}
\end{document}