# Another Sequence

1. Dec 23, 2008

### davee123

What's the next number?

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

DaveE

2. Dec 30, 2008

### davee123

Alright, more numbers in the sequence:

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

DaveE

3. Jan 1, 2009

### mabs239

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: Jan 1, 2009
4. Jan 5, 2009

### davee123

Ding!

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

5. Jan 6, 2009

### chaoseverlasting

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