I've only ever seen lower bound values given. E.g. http://mathoverflow.net/questions/93828/how-large-is-tree3 http://mathoverflow.net/questions/93828/how-large

I've only ever seen lower bound values given. E.g. http://mathoverflow.net/questions/93828/how-large-is-tree3 http://mathoverflow.net/questions/93828/how-large-is-tree3