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davee123
Dec23-08, 05:32 PM
What's the next number?

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

DaveE

davee123
Dec30-08, 10:56 PM
Alright, more numbers in the sequence:

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

DaveE

mabs239
Jan1-09, 03:17 AM
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.

davee123
Jan5-09, 10:34 AM
Every next number is the one next with more number of letters.

Ding!

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

chaoseverlasting
Jan6-09, 02:24 PM
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.