Grammatical codes of trees

A. Ehrenfeucht, G. Rozenberg
1991 Discrete Applied Mathematics  
Ehrenfeucht, A. and G. Rozenberg, Grammatical codes of trees, Discrete Applied Mathematics 32 (1991) 103-129. The problem of coding (chain free) trees by words where the length of the word coding a tree t equals the number of leaves of t is investigated. The notion of an insertive strict code is introduced and investigated-these are codes of a grammatical nature. It is shown that there are exactly 120 insertive strict codes. A characterization of these codes (and their various subclasses) is
more » ... en in grammatical terms. 0166-218X/91/$03.50 0 1991 -Elsevier Science Publishers B.V. (North-Holland)
doi:10.1016/0166-218x(91)90095-e fatcat:veangltf2bhazpegg5k63z4diu