Here we have all the programs from the two books:

Implementing Discrete Mathematics: Combinatorics and Graph Theory with Mathematica by Steven S. Skiena, Addison-Wesley Publishing Co., Advanced Book Program, 350 Bridge Parkway, Redwood City CA 94065. ISBN 0-201-50943-1.

This is the older two books and we have V0.9 code for that as CombinatoricaV0.9.m

The revised edition of this is:

Computational Discrete Mathematics: Combinatorics and Graph Theory in Mathematica, by Sriram V. Pemmaraju and Steven S. Skiena, Cambridge University Press, 2003.

We have V.2.0 or that as CombinatoricaV201.m

To run from inside Mathics3:

$ git clone [email protected]:Mathic3/Mathics3-Combinatorica.git
$ cd Mathics3-Combinatorica/Combinatorica

$ mathics

Mathics 7.0.1dev0
on CPython 3.12.10 ...
...

In[1]:= << "CombinatoricaV201"
Out[1]= None

In[2]:= Permutations[3]
Out[2]= {{1, 2, 3}, {1, 3, 2}, {2, 1, 3}, {2, 3, 1}, {3, 1, 2}, {3, 2, 1}}

In[3]:= Permute[{A,B,C,D}, Permutations[3]]
Out[3]= {{A, B, C}, {A, C, B}, {B, A, C}, {B, C, A}, {C, A, B}, {C, B, A}}

Although this version is newer, Mathics3 does hasn't yet caught up to the richer language that it uses. To use the version of the older book which handles graphics more completely:

In[1]:= << "CombinatoricaV091"
Out[1]= None

In[2]:= LexicographicPermutations[{1,2,3}]
Out[2]= {{1, 2, 3}, {1, 3, 2}, {2, 1, 3}, {2, 3, 1}, {3, 1, 2}, {3, 2, 1}}

In[3]:= LexicographicPermutations[{a,b,c}]
Out[2]= {{A, B, C}, {A, C, B}, {B, A, C}, {B, C, A}, {C, A, B}, {C, B, A}}