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Topic: An uncomputable finite number.
Replies: 2   Last Post: Apr 5, 2012 10:16 AM

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 Ben Bacarisse Posts: 368 Registered: 7/4/07
Re: An uncomputable finite number.
Posted: Apr 5, 2012 10:00 AM

Graham Cooper <grahamcooper7@gmail.com> writes:
<snip>
> More accurately, there is no such thing as uncomputable.

No, that's less accurate. Very much less accurate, in fact.

> It's like a painter saying a shade is uncolorable.
>
> It's entirely trivial that a computer program that
> checks_a_function_whether_it_itself_halts and does the opposite could
> not co-exist with a halt function.

No idea what this means, but please don't explain. Your view of
mathematics is so bizarre that there's no chance we can exchange ideas.

<snip>
> LOOK! It's a Busy Beaver! A non-computable number sequence!
>
> function BB(n) {
> firstTM = get1stTM#ofSize(n)
> lastTM = getlastTM#ofSize(n)
> asymptote = 0
> while(true) {
> for (tm=firstTM, tm++, tm<=lastTM) {
> retval = Run1Cycle(tm)
> if !null(retval) {
> if (find('0',retval)=0) { //unary output
> if(retval>asymptote) {
> asymptote=retval
> display(asymptote)
> }
> }
> }
> }
> }
> }

No, that does not compute BB(n). For one thing, it does not terminate
for any input.

Also, the only meaning I can give to this pseudo code runs only one
cycle of each machine (there's something like a tm++ after every call to
RunCycle(tm)). I know what you probably wanted to write, but I'll stick
to commenting on what you do write.

There's a general rule on Usenet. People who've solved many of the big
mathematics clear and, generally, sorted it all out once and for all,
never seem to have any grasp of detail. The rest of us are slaves
detail. If only we could free ourselves from getting the details
right, maybe we too could soar to your heights.

<snip>
--
Ben.

Date Subject Author
4/5/12 Ben Bacarisse
4/5/12 Graham Cooper