Naturals-util is a collection of data-structures and utility methods for dealing with natural numbers, especially with the {0, ..., n} domain.
This situation often arises when dealing with indexed or enumerated structures, for example transition systems with enumerated states.
You can either build the jar using gradle (see below) or fetch it from maven central:
<dependency>
<groupId>de.tum.in</groupId>
<artifactId>naturals-util</artifactId>
<version>0.19.0</version>
</dependency>
Build the project using gradle. All dependencies are downloaded automatically.
$ ./gradlew build