qregexp can't get match 'not preceeded by' to work

[kja]

Hi I can't figure out the regex to match any number not preceded by '['

I don't know why this doesn't work:

QRegExp n( "(?![)[0-9]+" );

I could also get the match I want by searching for a number not followed by ']' but I can't get that regex to work either:

QRegExp n( "[0-9]+(?!])" );

I have tried many variations of this, including escaping the ]'s like this --> "(?!\\])" --- but i can't get my match.

Just to be clear I want to match 150 but not [150].

Also, I would use "[^[]" but that would not match a number at the very beginning of the line.

What am I missing?
Thanks.