Hi,<BR><BR>I'm currently coding a function in Java that will find the number of possible combinations for a string. I've run into a problem in to a problem with regards to both speed and memory usage.

Some inventions operate in a recursive or iterative manner. This could be so of a machine that repeats actions or functions on a single article or to produce multiple articles, or operates on data.

In this article, we study some new characterizations of primitive recursive functions based on restricted forms of primitive recursion, improving the pioneering work of R. M. Robinson and M. D.