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/

Zendy Open

Presents the pdf analysis as premium feature

PDF Analysis

Insights

Presents the summarisation as premium feature

Summarisation

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Let  G  be a (2,  m, n )‐group and let  x  be the number of distinct primes dividing χ, the Euler characteristic of  G . We prove first that, apart from a finite number of known exceptions, a non‐abelian simple composition factor  T  of  G  is a finite group of Lie type with rank  n  ⩽  x . This result is proved using new results connecting the prime graph of  T  to the integer  x .  We then study the particular cases  x  = 1 and  x  = 2. We give a general structure statement for (2,  m, n )‐groups which have Euler characteristic a prime power, and we construct an infinite family of these objects. We also give a complete classification of those (2,  m, n )‐groups that are almost simple and for which the Euler characteristic is a prime power (there are four such).  Finally, we announce a result pertaining to those (2,  m, n )‐groups that are almost simple and for which |χ| is a product of two prime powers. All such groups which are not isomorphic to PSL 2 ( q ) or PGL 2 ( q ) are completely classified.

Orientably regular maps with Euler characteristic divisible by few primes