[Bug-wget] --spider output interpretation

[andreas wpv]

Can  you help me understand what this means? Just pulling the urls to build
a sitemap with it, but there is so much more in the output - and I cannot
find any documentation of the details in the output:

command:
wget --spider --recursive --no-verbose --no-parent -t 3
--output-file=wgetlog.txt $URL

example
2013-06-17 18:56:54 URL:http:/domain/file/19[149408/149408] ->
"domain/file/19.1" [1]


Bunch of questions:
1 what do numbers in brackets mean?
2. why is there a second url?
3. why is the second url modified with a '.1'  at the end?
4. what does the '[1]' at the end mean? Error code is kind of unlikely,
right?

Any info or link most appreciated.

andreas