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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The {\em atom-bond connectivity (ABC) index} is a degree-based graphtopological index that found chemical applications. The problem of completecharacterization of trees with minimal $ABC$ index is still an open problem.In~\cite{d-sptmabci-2014}, it was shown that trees with minimal ABC index donot contain so-called {\em $B_k$-branches}, with $k \geq 5$, and that they donot have more than four $B_4$-branches. Our main results here reveal that thenumber of $B_1$ and $B_2$-branches are also bounded from above by small fixedconstants. Namely, we show that trees with minimal ABC index do not containmore than four $B_1$-branches and more than eleven $B_2$-branches.

On structural properties of trees with minimal atom-bond connectivity index II