The Conjecture has been numerically checked for a large range of
values of n.
It is an interesting problem to find efficient algorithms to test the
conjecture on a computer.
The current record for verifying the Conjecture seems to be held
by Nabuo Yoneda at the University of Tokyo,
who has reportedly checked it for all
In several places the statement appears that A. S. Fraenkel has checked that
all have a finite total stopping time;
this statement is erroneous .