Then semi interior of any invariant subgroup of (Eq.
Then semi closure of any invariant subgroup of is an irresolute topological invariant subgroup again.
For cases 2-5, 9, 10, we use a particular fully invariant subgroup corresponding to the fundamental group of a torus or a Klein bottle that allows us to compute N(f) using fiberwise techniques.
1] with typical fiber N corresponding to a fully invariant subgroup of [[pi].
He reviews basic definitions of groups and operations with whole numbers, groups of permutation, the concept of isomorphism, cyclical subgroups of a given group, simple groups of movement, invariant subgroups
, homomorphic mappings, and partitioning a group relative to a given subgroup.