On Wednesday, August 22, 2018 at 11:05:15 PM UTC, John Clark wrote: > > On Wed, Aug 22, 2018 at 5:43 PM, <agrays...@gmail.com <javascript:>> > wrote: > > > >> *Can you write a function which is not computable? * > > > Yes, the Busy Beaver Function is not computable. We know that: > > BB(1) =1 > BB(2) =6 > BB(3) =21 > BB(4) =107 >
*You haven't *written* the function, just its alleged values for 1,2,3,4. What is the function? AG* > > But those are the only values we've be able to calculate with certainty, > the problem is the Busy Beaver function grows faster than any computable > function. We suspect that BB(5) is 47,176,870 but are far from certain and > BB(6) is at least 7.4*10^36534 and BB(7) is at least 10^10^10^10^10^7 but > could be much larger. Big as they are all Busy Beaver numbers are finite > but after a certain point they are not computable and nobody even knows > exactly where that point is. It has been proven that BB(7918) is not > computable but what is the smallest non computable-number? Nobody knows but > I wouldn't be surprised if it were BB(5). > > John K Clark > > > > > > -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.