Generalizations of Midy's theorem on repeating decimals.
Expansions in noninteger bases often appear in number theory and probability theory, and they are closely connected to ergodic theory, measure theory and topology. For two-letter alphabets the golden ratio plays a special role: in smaller bases only trivial expansions are unique, whereas in greater bases there exist nontrivial unique expansions. In this paper we determine the corresponding critical bases for all three-letter alphabets and we establish the fractal nature of these bases in dependence...
We consider positional numeration systems with negative real base , where , and study the extremal representations in these systems, called here the greedy and lazy representations. We give algorithms for determination of minimal and maximal -representation with respect to the alternate order. We also show that both extremal representations can be obtained as representations in the positive base with a non-integer alphabet. This enables us to characterize digit sequences admissible as greedy...