A Java Collatz graph drawing program - generates graphs of Collatz numbers ("3n + 1 problem") and draws the graphs using graphviz.

The interesting stuff is in the file Collatz.java above.

Requires Java 7 (JDK and JRE) and graphviz.

Run the ./run script with a single integer argument n, and a png will be output with the collatz graph including every integer up to n, plus any additional numbers generated by incorporating all numbers less than or equal to n into the graph:

./run CollatzRule 100

Alternatively run the following commands, plugging in whatever number you like to the second command:

javac collatz.java
java Main CollatzRule 100 > g.dot
dot -Tpng g.dot -o g.png

Either method generates an image file g.png with your graph.