You couldn't use that to compute the busy beaver function, as the busy beaver function asks about Turing machines which have unlimited tape. You can solve it if

You couldn't use that to compute the busy beaver function, as the busy beaver function asks about Turing machines which have unlimited tape. You can solve it if you have a finite amount of tape, but you'd never know whether one of machines that tried to exceed the limit would have produced a longer output before eventually halting.