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Lochs' theorem and its generalizations are conversion theorems that relate the number of digits determined in one expansion of a real number as a function of the number of digits given in some other expansion. In its original version, Lochs' theorem related decimal expansions with continued fraction expansions. Such conversion results can also be stated for sequences of interval partitions under suitable assumptions, with results holding almost everywhere, or in measure, involving the entropy. This is the viewpoint we develop here. In order to deal with sequences of partitions beyond positive entropy, this paper introduces the notion of log-balanced sequences of partitions, together with their weight functions. These are sequences of interval partitions such that the logarithms of the measures of their intervals at each depth are roughly the same. We then state Lochs-type theorems which work even in the case of zero entropy, in particular for several important log-balanced sequences of partitions of a number-theoretic nature. [ABSTRACT FROM AUTHOR]

A (0, 1)-matrix has the consecutive-ones property (C1P) if its columns can be permuted to make the 1’s in each row appear consecutively. This property was characterized in terms of forbidden submatrices by Tucker in 1972. Several graph classes were characterized by means of this property, including interval graphs and strongly chordal digraphs. In this work, we define and characterize 2-nested matrices, which are (0, 1)-matrices with a variant of the C1P and for which there is also a certain assignment of one of two colors to each block of consecutive 1’s in each row. The characterization of 2-nested matrices in the present work is of key importance to characterize split graphs that are also circle by minimal forbidden induced subgraphs. [ABSTRACT FROM AUTHOR]