Groups with commuting inner mappings are of nilpotency class at most two, but there exist loops with commuting inner mappings and of nilpotency class higher than two, called loops of Csörgő type. In order to obtain small loops of Csörgő type, we expand our programme from Explicit constructions of loops with commuting inner mappings, European J. Combin. 29 (2008), 1662–1681, and analyze the foll...

We prove a conjecture made by Brundan and Kleshchev on the nilpotency degree of cyclotomic quotients of rings that categorify one-half of quantum sl(k).

A one-dimensional cellular automaton is a dynamical system which consisting in a juxtaposition of cells whose state changes over discrete time according to that of their neighbors. One of its simplest behaviors is nilpotency: all configurations of cells are mapped after a finite time into a given “null” configuration. Our main result is that nilpotency is equivalent to the condition that all co...

We introduce left and right series of semi-braces. This allows to define nilpotent study the structure such semi-braces generalize some results, known for skew braces, B that set additive idempotents E is an ideal . Finally we concept a semi-brace show multiplicative group nilpotent.

We take a step towards the development of a nilpotency theory for loops based on the commutatorassociator filtration instead of the lower central series. This nilpotency theory shares many essential features with the associative case. In particular, we show that the isolator of the nth commutator-associator subloop coincides with the nth dimension subloop over a field of characteristic zero. Th...

Let G be a finite p-group of nilpotency class 2. We find necessary and sufficient conditions on G such that each central automorphism of G fixes the center of G element-wise.