In this paper we deal with the following problems: When do the solutions of a collection of differential equations satisfy an elementary relation, that is, when is there an equation of the form R = 0 ...

Applicable Analysis and Discrete Mathematics, Vol. 10, No. 2 (October 2016), pp. 408-446 (39 pages) An associative Boolean tree is a plane rooted tree whose internal nodes are labelled by AND or OR ...