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  • What's the next term?

  • In the following sequence it goes 148 48 88 4 88 What's the next term?

  • Which actually is very easy and why that's not so obvious?

  • Well, well, it's a little strange for 8 48 88 for a date, and obviously the next one is going to be 888 and then 4888 The right way to look at this.

  • It's to stare at these numbers.

  • Look at this number.

  • What do you see?

  • Well, you see eight.

  • But more important, you see two holes.

  • When you look at 48 you see three holes.

  • 88 has four holes in it.

  • Four has one home if you draw affords that way, and one has no holes in it.

  • So the definition of this sequence is it's the smallest positive number that has n holds in it.

  • People always get really funny about sequences and numbers that are sort of based 10 specific.

  • This is This is how you draw your numbers specifically.

  • If you draw your four non enclosed, it would be it would change the sequence.

  • In that case, if you for is not enclosed.

  • Then you would make it 168 68 88 688 and so on.

  • And if you do your twos in a very fancy way with a hole in them, then the six could be replaced by two.

  • This is topology him.

  • What we're doing is petitioning the piece of paper in tow parts without using numbers.

  • So if you write down a four, you've partitioned the plane into two pods, this part on the outside.

  • So it's topology.

  • This one is another base 10 sequence, so but it's lovely.

  • 61 2182 43 3 And the question is, what comes next?

  • Don't get distracted into looking for something that's too complicated.

  • Watch carefully.

  • There's nothing up my sleeve.

  • I'm just going to move the calmer, and I'm gonna move that calmer than that that come up and there's an invisible zero.

  • And so the next one.

  • Get it?

  • 6 12 18 24 30 say 36.

  • So that one after that would be 42.

  • They're multiples of six.

  • Nothing could be simpler, but if you were misled into looking for something complicated you wouldn't get that is sneaky.

  • That one.

  • Yeah, yeah, yeah, yeah, I like it.

  • It's misleading.

  • It's deceptive.

  • Slight of hand one.

  • We get zero to forget.

  • Sierra three, we get zero for we get zero.

  • This doesn't look too promising.

  • All right?

  • Is it ever going to get more than Sarah yet?

  • Five.

  • We get four six, we get 97 you get five eight to get 19 we get one 10.

  • I'll do a couple more to make.

  • 10.

  • We get 0 11 You'll never guess what we get for 11 55.

  • What's the rule?

  • Let me show you the answer.

  • I put the squares on top of the numbers and you look through the window.

  • You have to think like a room.

  • The ivy.

  • Four.

  • I hex.

  • Nine.

  • The five 81 There's a single 1910 is nothing.

  • 11 is 55 so on.

  • That would have taken me a year s.

  • So, of course, it might not be a legal Roman number.

  • You might have the ones and the V's and the M's in the wrong order.

  • In which case, the way the sequence would be defined as you say that zero for that too.

  • closely related sequences in the sense that they both have names.

  • They both have slightly misleading names.

  • Titles on the 1st 1 the even numbers.

  • Well, you know what the even numbers are.

  • 2468 But I would like you to figure out what the even numbers are, too.

  • I have to be very careful for 677 is not even 89 10 11 12 12 30 It's the next even number.

  • And then 32 34 36 40 42 44 50 52 54 56.

  • You getting the idea?

  • 60.

  • Let me continue 60 to 64.

  • 66 2000.

  • There's any even numbers.

  • 2000.

  • That was a jump.

  • Why are those three even numbers?

  • What do you notice about these numbers?

  • For one thing, they're all even.

  • The second thing is that if you if you write out the number in English, there are no ease in them.

  • One is missing because one has an E in it.

  • Three has an e in it ate, hasn't he in it?

  • In fact, there's a theory.

  • Um, it's an old theorem of mine.

  • Every hard number contains an e.

  • And you can easily prove that by looking at all the odd numbers and check why they called even numbers e is banned and the other questions Let me show you another one with a name.

  • These are the e mopes, and again the name is a hint, and in this case, it's actually a legitimate hint theme.

  • Herbs, as you might guess.

  • Well, let me show you what they look like, first of all, and then you can guess.

  • 13.

  • 17 then, um, her.

  • It's not 19.

  • You might have thought I was gonna write 19 but it's actually 31 37 71 that's probably enough of a hint.

  • Well, obviously they're primes.

  • And if you look at the name, you see its prime backwards.

  • So these are the primes, which, when you read them backwards, are still primes but different crimes.

  • So we don't put out 11 because it's palindrome.

  • Make thes of primes, which, when you read it backwards, gives you a different crime.

  • I know what you're all thinking.

  • Everyone.

  • What is the largest known e Murph?

  • A sw.

  • Far as I can tell, it's this or its decimal expansion.

  • Is this nephew like these fun little puzzles.

  • I've actually got one left over, one that got cut from this video, but still pretty good fun.

  • I've put it over on the number filed to channel.

  • There's links on the screen and in the description, and we'll have new Sloan back really soon.

  • Talking about Maur amazing sequences from his online encyclopedia.

  • Stay tuned for that.

What's the next term?

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