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  • So we're gonna do a classic number foul video where we talk about a number on a property of that number.

  • Today's number is 196.

  • What's special?

  • About 196.

  • We're gonna do a process called reverse and at it's very simple.

  • No, again, you can do it.

  • So we're gonna take a number.

  • What number shall we take?

  • Give me a two digit 2023.

  • We're gonna reverse an ad.

  • So I'm gonna reverse the digits.

  • So it's 32 add them together.

  • And if I'm correct, it's 55.

  • Okay, I'm going to stop there because this is a palindrome number.

  • So it's the same forwards and back.

  • That's what I want to get to this, even do another number.

  • Maybe it'll take a bit longer to get to a palindrome.

  • What?

  • The number could re pick speaker.

  • Three digit number.

  • 254 3 Add 452 706.

  • So we haven't got a palindrome number yet, so we might have to do that again to retake the results and apply to get 1st 607 That's together.

  • What do we get so one for you want three?

  • It's not pun dream yet.

  • Might do another step.

  • Question is, how many steps is this going to take?

  • So we add these together.

  • Hey, Eddie took a couple of steps.

  • 4444 Well, numbers end up finally or eventually with a palindrome.

  • It turns out all two digit numbers do end up in a palindrome or three digit numbers.

  • We're not so sure about facts.

  • The number 196 is the smallest number that we don't know if it ends in a palindrome or not.

  • When you repeat this process on, we've tried for a 1,000,000,000 interational.

  • We've done this over and over and over more than a 1,000,000,000 interational on.

  • Still, it hasn't ended in a palindrome.

  • Will it ever a number that doesn't end in a palindrome.

  • It's called a large, shrill number.

  • 196 appears to be a lush well number, obviously the smallest one, but we're not sure we don't know.

  • It's not proved.

  • We've just checked it a lot.

  • It's a most numbers.

  • Take 34 steps.

  • Not, you know, not long.

  • 89 89.

  • An interesting one.

  • It takes 24 steps to finally get to be a palindrome number.

  • I'm pausing in case, Brady says.

  • Go on In case Brady made me do it, I did make a note off that better.

  • I haven't got him quite finished it yet, but Brady isn't going to make me do it five times because we will be here for a long time.

  • Took me ages to delist 196.

  • Might be one of these lists.

  • Are there any definitely showrooms?

  • There are no definite lush round numbers.

  • We've got a list of candidates only now I'm told about in lower basis, and we talk about base to base three and base for.

  • You can show numbers that definitely going to one of these loops, or we'll never end up in a palindrome I.

  • It turns out that based 10.

  • Not only that, the base we use in day to day life, but it's the smallest interesting case for this.

  • It's the smallest base that we're not sure if we can do it or not.

  • In the smaller bases, apparently, we have an answer.

  • Yeah, 196 is the smallest candidate.

  • The next one, 295.

  • The next one is 394 and it's 496.

  • Not irregular spot every 100 or so.

  • This is quite a few of these.

  • Maybe some of them are in the shroud numbers, and some of them might just finally become a palindrome at some great distance away.

  • We don't know the next one might be more obvious because we started with 196.

  • It's palindrome automatically is one of these candidates as well, and so on and so on.

  • Yes, we've checked 196 for billions of it orations.

  • The numbers get larger every time you do it at the numbers are now something like 600 million digits long the shroud and despite a way that name Lush Well, let's write that down That came from one of the investigators in this problem is actually a kind of rough but not quite anagram off his girlfriend's name.

  • Which is Cheryl Oh, Cheryl strikes again.

  • Why do we do this?

  • There's no application there, right?

  • We do this for you, for fun, for the exercise, for the mental exercise, for the practice off it maybe It turns out that if there's a proof the proof might use techniques that are deeper than the problem looks on its surface on, we can apply those two serious problems.

  • This problem became kind of famous in the 19 eighties in the community off hobbyist micro computer programmers.

  • So they were using this to test out their micro computer programming skills on DSO.

  • They would make these lists off these reverse and add algorithms.

  • They make these lists.

  • And of course, all you need is when you want to pass on the baton or pass on the torch to the next person, you just need the last entry or you just just give him the last entry and then they can carry on the process.

  • And that's what's happened since theeighties this process.

  • This battle has been passed from person to person.

  • Currently, we are on these huge numbers, and still it hasn't been resolved yet.

  • We'd like to thank audible dot com for their support of this number five video, and with over 180,000 titles in their library, it is the best place to go for audio books and other spoken materials.

  • Now I'm inaudible custom myself.

  • I especially enjoyed listening when I'm out.

  • Walking the dogs as I've spoken about before, or embarking on a really long drive across the country really makes the whole drive a lot more enjoyable.

  • Now, various number file stars have books on Audible.

  • I'm gonna put some links to them in the video description so you can check them out.

  • Or, if you're after one with a very number title, you can read the one I'm reading at the moment, which is 11 22 63.

  • It's a really interesting book by Stephen King about time travel on also deals with the Assassination of John F.

  • Kennedy.

  • It also weighs in at over 30 hours long and abridged, so I'm getting plenty of dog walks out of that one.

  • Now.

  • If you were interested in checking out Audible and you really should goto audible dot com slash number file, then they'll know you came from here, and that's good.

  • And when you saw it on, you get a free audiobook at the start, so you get your 1st 1 for free.

  • You can see what you think of the whole thing.

  • It's a great service.

So we're gonna do a classic number foul video where we talk about a number on a property of that number.

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