Warning: This draft is draftier than you might expect. More specifically, • Some sections are missing. • Many sections are incomplete. In most cases the incompleteness is noted, but occasionally it isn’t. • Some sections were written nearly two years ago, and are now outdated. • There are not yet enough citations to similar work of other people. Despite all this, there’s probably enough deciphe...

Codes with various kinds of decipherability, weaker than the usual unique decipherability, have been studied since multiset decipherability was introduced in mid-1980s. We consider decipherability of directed figure codes, where directed figures are defined as labelled polyominoes with designated start and end points, equipped with catenation operation that may use a merging function to resolve...

In this paper, we study the inverse problem for Dirac differential operators with  discontinuity conditions in a compact interval. It is shown that the potential functions can be uniquely determined by the value of the potential on some interval and parts of two sets of eigenvalues. Also, it is shown that the potential function can be uniquely determined by a part of a set of values of eigenfun...