One-Variable Word Equations and Three-Variable Constant-Free Word Equations
: Nowotka D, Saarela A
Publisher: WORLD SCIENTIFIC PUBL CO PTE LTD
: 2018
: International Journal of Foundations of Computer Science
: INTERNATIONAL JOURNAL OF FOUNDATIONS OF COMPUTER SCIENCE
: INT J FOUND COMPUT S
: 29
: 05
: 935
: 950
: 16
: 0129-0541
: 1793-6373
DOI: https://doi.org/10.1142/S0129054118420121(external)
: https://research.utu.fi/converis/portal/detail/Publication/35741481(external)
We prove connections between one-variable word equations and three-variable constant-free word equations, and use them to prove that the number of equations in an independent system of three-variable constant-free equations is at most logarithmic with respect to the length of the shortest equation in the system. We also study two well-known conjectures. The first conjecture claims that there is a constant c such that every one-variable equation has either infinitely many solutions or at most c. The second conjecture claims that there is a constant c such that every independent system of three-variable constant-free equations with a nonperiodic solution is of size at most c. We prove that the first conjecture implies the second one, possibly for a different constant.