Undecidability in matrices over Laurent polynomials\
: Halava V, Harju T
Publisher: ACADEMIC PRESS INC ELSEVIER SCIENCE
: 2004
: Advances in Applied Mathematics
: ADVANCES IN APPLIED MATHEMATICS
: ADV APPL MATH
: 33
: 4
: 747
: 752
: 6
: 0196-8858
DOI: https://doi.org/10.1016/j.aam.2004.04.002
We show that it is undecidable for finite sets S of upper triangular (4 x 4)-matrices over Z[x, x(-1)] whether or not all elements in the semigroup generated by S have a nonzero constant term in some of the Laurent polynomials of the first row. This result follows from a representations of the integer weighted finite automata by matrices over Laurent polynomials. (C) 2004 Elsevier Inc. All rights reserved.