The LEDA Library - LEDA is a library of the data types and algorithms of combinatorial computing.
ACE - An Algebraic Combinatorics Environment for MAPLE providing functions to work with classical structures in algebraic combinatorics. Free download..
Combinatorics Software of the Algorithms Project - Combinatorial analysis, discrete mathematics and computer algebra are the main interests of the Algorithms Projects. The packages let you define combinatorial structures; manipulate the associated generating functions, functional equations or recurrences; study their asymptotic behaviour..
Free Software in Graph Theory - Free Software for Win 9X,NT on Graph Theory by Vitali Petchenkine. Procedures: Metrics of the graph; Paths and cycles; Colorations; Automorphism group; Minimal spanning tree; Shortest paths; Max. Capacity path; K Shortest paths; Salesman problem; Maximal flow; Critical path; Reports for Graphs; Print..
Gato: The Graph Animation Toolbox - Software for visualizing graph algorithms. Free under GPL. Unix, Linux, MacOs ad Windows versions..
GeoSteiner - Software for computing Steiner trees. Written in ANSI C, includes the public domain LP-solver lp_solve..
GOBLIN Graph Library - C++ library of graph optimization algorithms with a GUI for editing, running and tracing the algorithms..
GRAPE - A GAP package for computing with graphs; primarily designed for the efficient construction and analysis of graphs related to groups, combinatorial designs and finite geometries..
Graph Coloring By DSATUR - By using the DSATUR algorithm, this php/form colors any graph in the Dimacs format..
Graph Magics - A tool for graph theory, having a generator and offering various algorithms: shortest paths, network flows, maximal clique, optimal coloring etc..
Graph Partitioners - Three algorithms written in NESL for finding separators of graphs, in order to compare the quality of the cuts..
GraphThing - Tool for investigating Graph Theory, with a GTK interface. Free under GPL. Unix, source code in C++..
graph-utils - A set of small utilities realizing theoretical graph algorithms (including tree algorithms). The utilities work with simple text input/output formats..
JGraphT - Free Java class library that provides mathematical graph-theory objects and algorithms..
LINK: A Software System for Discrete Mathematics - A general-purpose, extendible computing environment in which discrete mathematical objects representing real world problems can be easily manipulated and visualized..
Nauty - A program for computing automorphism groups of graphs and digraphs. It can also produce a canonical labelling..
plantri and fullgen - Programs for generation of certain types of planar graph, generated in such a way that exactly one member of each isomorphism class is output without the need for storing them..
Project Vega - A system for manipulating discrete mathematical structures: a Mathematica based collection of operations with interface to external packages and programs..
SCL - star complement library - A program for calculating the maximal graphs using the star complement technique. The programs for computing the maximal cliques and isomorphism classes of graphs are included..
SF, Posets and Coxeter/Weyl - John Stembridge's Maple packages for symmetric functions, posets, root systems, and finite Coxeter groups..