Hi I am a stata beginner.

I want to extract observations satisfying several conditions but it is really hard for me.
The conditions are below.

v1 ==1 when wave ==1 and v1==0 when wave ==2 or 3 or 4 or 5 or 6
where v1 is a dummy variable having 1 or 0 and wave is the wave in panel data.

In a sentence, I want the observations who retired in wave1 but were reemployed in wave2 or ... or wave6 (v1 indicates retirement)

I tried a lot of ways but, you know, it was too hard for a beginner
Please, help me!!