As I am in severe 'back of the envelope' mode, I did not investigate that claim. But I think they refer to footnote 21 for the estimate: http://people.csail.mi

As I am in severe 'back of the envelope' mode, I did not investigate that claim. But I think they refer to footnote 21 for the estimate: http://people.csail.mit.edu/tromer/papers/factorest.pdf http://people.csail.mit.edu/tromer/papers/factorest.pdf