What's the Pattern in This Sequence of Numbers?

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Discussion Overview

The discussion revolves around identifying a pattern in a sequence of numbers provided by the user, with a focus on the nature of the sequence and its potential mathematical properties. Participants explore various hypotheses regarding the sequence's structure, including its relationship to prime numbers and the number of letters in the numerical representations.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant, DaveE, presents an initial sequence and asks for the next number.
  • Another participant suggests that the sequence may involve numbers with an increasing count of letters in their written form.
  • There is a mention that the first sequence contains prime numbers, except for the number 1, which is described as "sort of a prime number" based on certain technicalities.
  • Participants express uncertainty about how prime numbers relate to the sequence, with one noting that this aspect led to confusion.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the pattern of the sequence, and multiple competing views regarding its structure and properties remain present.

Contextual Notes

There are unresolved assumptions regarding the definitions of prime numbers and the criteria for determining the next number in the sequence based on letter counts.

davee123
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What's the next number?

1, 3, 11, 13, 17, 23, 73, ?

DaveE
 
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Alright, more numbers in the sequence:

1, 3, 11, 13, 17, 23, 73, 101, 103, 111, 113, 117, 123, 173, 323, 373, ?

DaveE
 
A really teasing sequence.

Though I am trying to figure out for so many days, but failed. Anyway I would make a blind guess:


No, wait a minute:

...1103, 1111, 1113, 1117, 1123, 1173, 1323, 1373, 3323, 3373, 11373, 13323, 13373, 17373, 23323, 23373, 73373, 101373, 103323, 103373, 111373, 113323, 113373, 117373

Not my own work ;)

Every next number is the one next with more number of letters.

It added to the confusion that the first sequence contains prime numbers except the first one.
 
Last edited:
mabs239 said:
Every next number is the one next with more number of letters.

Ding!

mabs239 said:
It added to the confusion that the first sequence contains prime numbers except the first one.

I didn't even notice that, but that's an interesting point! The first 9 numbers are all coincidentally prime, excluding 1, which is sort of a prime number anyway on certain technicalities.

I think I had heard some variant on the sequence before, but I couldn't seem to find it, so I figured it'd be worth posting...

DaveE
 
davee123 said:
I didn't even notice that, but that's an interesting point! The first 9 numbers are all coincidentally prime, excluding 1, which is sort of a prime number anyway on certain technicalities.

DaveE

Thats what lead me off. I was wondering how primes fit into all of it.
 

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