Some Identities Concerning the Function Subst [x; y; z]
Revised March 1962
The purpose of this paper is two-fold; 1) to explore the use of recursion induction in proving theorem about functions of symbolic expressions, in particular. 2) to investigate thoroughly the algebraic properties of the LISP function subst [x; y; z] by this method. The main result is embodied in Theorem 8.