Form equivalence class Howard-Rubin Number: 1

Statement:

Strong Nielsen-Schreier Theorem II: If \(G\) is a group which is freely generated by \(X\) and \(U\) is a subgroup of \(G\),then there is a subset \(A\) of \(G\) which freely generates \(U\) and is level with respect to \(X\).

Howard-Rubin number: 1 BB

Citations (articles): Howard [1985] Subgroups of a free group and the axiom of choice

Connections (notes): Note [129] In this note we give definitions concerning free groups for forms [1 BB], [1 CA], Form 68 and Form 348.

References (books):

Back