The number perl script will print the English name of a number. One can print names of extremely large numbers (e.g. 1e1234567). Number can be run on the command line, or as a CGI script when run as 'number.cgi'. Number prints names in both the American and European naming system. It can also print the decimal expansion of a number in either naming system.
OBJ3 is a program specification and proof system based on order sorted equational logic. It has been successfully used for research and teaching in software design and specification, rapid prototyping, theorem proving, user interface design, and hardware verification, among other things. It was the first language to implement parameterized programming and its module system influenced the designs of the Ada, C++, and ML module systems.
PARI/GP is a package aimed at efficient computations in number theory, containing a large number of other useful functions. It is somewhat related to a Computer Algebra System, but is not really one since it treats symbolic expressions as mathematical entities such as matrices, polynomials, series, etc., and not as expressions per se. However it is often much faster than other CAS, and contains a large number of specific functions not found elsewhere, essentially for use in number theory.
R is a language and environment for statistical computing and graphics. It is similar to S, which was developed at Bell Laboratories by John Chambers et al. It provides a wide variety of statistical and graphical techniques (linear and nonlinear modelling, statistical tests, time series analysis, classification, clustering, etc.). R is designed as a true computer language with control-flow constructions for iteration and alternation, and it allows users to add additional functionality by defining new functions. For computationally intensive tasks, Fortran and C code can be linked and called at run time.
rcalc is a fast and light symbolic calculator for the GNOME desktop environment which aims to occupy the middle ground between simple point-and-click calculators and full featured mathematical packages. The emphasis is on useability; adding up should be as simple as on a handheld calculator, yet the more complex features should be there as required.