question on using the -n option for sorting

[American Citizen]

Hello:

I am a number theory mathematician, using linux as a computer platform 
for my studies.

In using the sort command with the -n option, such as the command

%sort -k3,3n close.2 > close.3

I noticed that the 93 digits in the 3rd field are NOT numerically 
ordered, although most were.

I switched to the dictionary order

%sort -k3,3 close.2 > close.3

and then close.3 seems to be in the correct numerical sequence in field 3.

Can anyone share with me how many digits the -n option can safely sort? 
Can we do decimals > 17 digits with this option? Can sort be 
strengthened to handle digits > 17 ?

Thank you for letting me know. I attach a short 100 line sample file 
which was extracted from the 29,984 line actual close.2 file.

Randall

example.sort
Description: Text document