BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250724T073810EDT-3165RusavU@132.216.98.100 DTSTAMP:20250724T113810Z DESCRIPTION:On a conjecture about regularity and $\ell$-abelian complexity. \n\nSince the fundamental work of Cobham\, the so-called automatic sequenc es have been extensively studied. A natural generalization of automatic se quences over an infinite alphabet is given by the notion of $k$-regular se quences\, introduced by Allouche and Shallit in 1992. The $k$-regularity o f a sequence provides us with structural information about how the differe nt terms are related to each other. We show that a sequence satisfying a c ertain symmetry property is 2-regular. We apply this theorem to develop a general approach for studying the ℓ-abelian complexity of 2-automatic sequ ences. In particular\, we prove that the period-doubling word and the Thue –Morse word have 2-abelian complexity sequences that are 2-regular. Along the way\, we also prove that the 2-block codings of these two words have 1 -abelian complexity sequences that are 2-regular. The computation and argu ments leading to these results fit into a quite general scheme that we hop e can be used again to prove additional regularity results.\n DTSTART:20170310T183000Z DTEND:20170310T193000Z LOCATION:Room PK-4323\, CA\, Pavillon Président-Kennedy SUMMARY:Élise Vandomme\, Université du Québec à Montréal URL:/mathstat/channels/event/elise-vandomme-universite -du-quebec-montreal-266724 END:VEVENT END:VCALENDAR