The string number of self-maps arose in the context of algebraic entropy and it can be viewed as a kind of combinatorial entropy function. Later on, its values for endomorphisms of abelian groups were calculated in full generality. We study its global version for abelian groups, providing several examples involving also Hopfian abelian groups. Moreover, we characterize the class of all abelian groups with string number zero in many cases and discuss its stability properties.
机构:
Open Univ, Dept Math & Stat, Milton Keynes MK7 6AA, Bucks, EnglandOpen Univ, Dept Math & Stat, Milton Keynes MK7 6AA, Bucks, England
Grannell, M. J.
Knor, M.
论文数: 0引用数: 0
h-index: 0
机构:
Slovak Tech Univ Bratislava, Dept Math, Fac Civil Engn, Bratislava 81368, SlovakiaOpen Univ, Dept Math & Stat, Milton Keynes MK7 6AA, Bucks, England
机构:
Open Univ, Dept Math & Stat, Milton Keynes MK7 6AA, Bucks, EnglandOpen Univ, Dept Math & Stat, Milton Keynes MK7 6AA, Bucks, England
Grannell, M. J.
Knor, M.
论文数: 0引用数: 0
h-index: 0
机构:
Slovak Tech Univ Bratislava, Dept Math, Fac Civil Engn, Bratislava 81368, SlovakiaOpen Univ, Dept Math & Stat, Milton Keynes MK7 6AA, Bucks, England