Towards parametrizing word equations
RAIRO. Theoretical Informatics and Applications, Tome 35 (2001) no. 4, pp. 331-350

Classically, in order to resolve an equation u≈v over a free monoid X * , we reduce it by a suitable family ℱ of substitutions to a family of equations uf≈vf, f∈ℱ, each involving less variables than u≈v, and then combine solutions of uf≈vf into solutions of u≈v. The problem is to get ℱ in a handy parametrized form. The method we propose consists in parametrizing the path traces in the so called graph of prime equations associated to u≈v. We carry out such a parametrization in the case the prime equations in the graph involve at most three variables.

De façon classique, on résout une équation u≈v dans le monoïde libre X * en la réduisant par une famille convenable ℱ de substitutions en une famille d’équations uf≈vf, f∈ℱ, chacune en moins de variables que u≈v, et ensuite en combinant des solutions des uf≈vf pour obtenir des solutions de u≈v. Le problème qui se pose alors est d’obtenir ℱ sous une forme commode paramétrisée. La méthode que nous proposons est basée sur la paramétrisation des traces des chemins dans le graphe des équations premières associé à u≈v. Nous effectuons une telle paramétrisation dans le cas où les équations premières dans le graphe contiennent au plus trois variables.

Classification : 68R15, 20M05
Keywords: equation, free monoid, parametrization, universal family
@article{ITA_2001__35_4_331_0,
     author = {Abdulrab, H. and Goral\v{c}{\'\i}k, P. and Makanin, G. S.},
     title = {Towards parametrizing word equations},
     journal = {RAIRO. Theoretical Informatics and Applications},
     pages = {331--350},
     year = {2001},
     publisher = {EDP-Sciences},
     volume = {35},
     number = {4},
     mrnumber = {1880803},
     zbl = {1112.68434},
     language = {en},
     url = {https://www.numdam.org/item/ITA_2001__35_4_331_0/}
}
TY  - JOUR
AU  - Abdulrab, H.
AU  - Goralčík, P.
AU  - Makanin, G. S.
TI  - Towards parametrizing word equations
JO  - RAIRO. Theoretical Informatics and Applications
PY  - 2001
SP  - 331
EP  - 350
VL  - 35
IS  - 4
PB  - EDP-Sciences
UR  - https://www.numdam.org/item/ITA_2001__35_4_331_0/
LA  - en
ID  - ITA_2001__35_4_331_0
ER  - 
%0 Journal Article
%A Abdulrab, H.
%A Goralčík, P.
%A Makanin, G. S.
%T Towards parametrizing word equations
%J RAIRO. Theoretical Informatics and Applications
%D 2001
%P 331-350
%V 35
%N 4
%I EDP-Sciences
%U https://www.numdam.org/item/ITA_2001__35_4_331_0/
%G en
%F ITA_2001__35_4_331_0
Abdulrab, H.; Goralčík, P.; Makanin, G. S. Towards parametrizing word equations. RAIRO. Theoretical Informatics and Applications, Tome 35 (2001) no. 4, pp. 331-350. https://www.numdam.org/item/ITA_2001__35_4_331_0/

[1] J. Jaffar, Minimal and Complete Word Unification. J. ACM 37 (1990) 47-85. | Zbl | MR

[2] Yu.I. Hmelevskiĭ, Equations in free semigroups. Trudy Mat. Inst. Steklova 107 (1971); English Translation in Proc. Steklov Inst. Math. 107 (1971) 1976. | Zbl | MR

[3] A. Lentin, Équations dans les monoïdes libres. Gautier-Villars, Paris (1972). | Zbl | MR

[4] M. Lothaire, Combinatorics on Words. Addison-Wesley (1983). | Zbl | MR

[5] G.S. Makanin, The problem of solvability of equations in a free semigroup. Mat. Sbornik 103 (1977) 147-236 (in Russian); English Translation in Math. USSR Sbornik 32 (1977) 128-198. | Zbl | MR

[6] G.S. Makanin, On general solution of equations in free semigroups, in Proc. of IWWERT'91, edited by H. Abdulrab and J.P. Pécuchet. Springer, Lecture Notes in Comput. Sci. 677, 1-5. | Zbl

[7] G. Plotkin, Building-in Equational Theories. Machine intelligence 7 (1972) 73-90. | Zbl