English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Quasi-trees generalize trees in that the unique "path" between two nodes maybe infinite and have any countable order type. They are used to define therank-width of a countable graph in such a way that it is equal to the leastupper-bound of the rank-widths of its finite induced subgraphs. Join-trees arethe corresponding directed trees. They are useful to define the modulardecomposition of a countable graph. We also consider ordered join-trees, thatgeneralize rooted trees equipped with a linear order on the set of sons of eachnode. We define algebras with finitely many operations that generate (viainfinite terms) these generalized trees. We prove that the associated regularobjects (those defined by regular terms) are exactly the ones that are theunique models of monadic second-order sentences. These results use andgeneralize a similar result by W. Thomas for countable linear orders.

Algebraic and logical descriptions of generalized trees