On sequences resulting from iteration of modified quadratic and palindromic mappings

Anton Černý
1997 Theoretical Computer Science  
Blanchard and Fabre (1994) have considered description of symbolic systems by sequences obtained by iteration of two mappings $1, and d" defined by g,(u) = u [u], and L/, J u[u]:, m here the word [u], is obtained from a word u by removing the last ,j symbols. They stated a conjecture thal the iteration of (I, results in an automatic sequence. We prove here that t/, ix. while (1) 1s not, a 2.automatic sequence. Our result is obtained by investigation of two wider classes of sequences. *
doi:10.1016/s0304-3975(96)00294-0 fatcat:5plp4fxjebg2bhqvfsadufcfuq