You were very close. This will do what you want: 

/^N(?!.*00$).*$/

[download]
If you want to capture the match, then use $1 if the following evaluates to true 
/^(N(?!.*00$).*)$/

[download]

Update: If we had ham, we could have ham and eggs, if we had eggs.

the lowliest monk

In reply to Re: ^N.*(?!00$) by tlm
in thread ^N.*(?!00$) by ady

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