Summary
A binary operation on the class of trees is defined that generates a set B of finite trees form a trivial tree (one node) and B contains for every finite tree G exactly one element isomorphic to G. The binary operation defines an algebraic structure on B, and as a consequence the finite tree types are characterized as an initial algebra in the same way as the natural numbers are characterized as an initial algebra by the Peano-Lawvere axiom [2]. Simple and primitive recursion are defined and some applications of the initial algebra characterization are given.
Similar content being viewed by others
References
Arbib, M.A., Manes, E.G.: Arrows, structures and functors. New York: Academic Press 1975
Birkhoff, G., MacLane, S.: Algebra. New York: Macmillan 1968
Comtet, L.: Advanced combinatorics. Boston: Dordrecht 1974
Goguen, J.A., Thatcher, J.W., Wagner, E.G.: An initial algebra approach to the specification, correctness and implementation of abstract data types. IBM Research Report RC 6487, 1977
Eilenberg, S., Wright, J.B.: Automata in general algebras. Information and Control 11, 452–470 (1967)
Give'on, Y., Arbib, M.A.: Algebra automata. II. The categorical framework for dynamic analysis. Information and Control 12, 346–370 (1968)
Grätzer, G.: Universal algebra. Princeton: Van Nostrand 1968
Harary, F., Plamer, E.M.: Graphical enumeration. New York: Academic Press 1966
MacLane, S.: Categories for the working mathematician. Berlin-Heidelberg-New York: Springer 1972
Mezei, J., Wright, J.B.: Generalized ALGOL-like languages. IBM Research Report RC 1528, 1965
Oberschelp, W., Wille, D.: Mathematischer Einführungskurs für Informatiker. Stuttgart: Teubner 1976
Pareigis, B.: Categories and functors. New York: Academic Press 1970
Schmidt, J.: Mengenlehre, Bd. I. Mannheim: B.I. 1966
Thatcher, J.W.: Characterizing derivation trees of context-free grammars through a generalization of finite automata theory. J. Comput. System Sci. 1, 317–322 (1967)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Merzenich, W. A binary operation on trees and an initial algebra characterization for finite tree types. Acta Informatica 11, 149–168 (1979). https://doi.org/10.1007/BF00264022
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00264022