An Analogue of the Strengthened Hanna Neumann Conjecture for Virtually Free Groups and Virtually Free Products

The Friedman--Mineyev theorem, earlier known as the (strengthened) Hanna Neumann conjecture, gives a sharp estimate for rank of intersection two subgroups in free group. We obtain an analogue this inequality any virtually group (or, more generally, containing product left-orderable groups finite-index subgroup).