3 separate stretches
Names whose record falls into exactly 3 unbroken stretches, separated by years with no ranking at all.
A stretch ends when no registrar ranked the name that year. That almost always means it fell below a published list's cut-off, never that no child received the name, and never that it returned for any particular reason. Registrars also publish to different depths, so a name can leave one list while staying in another.
1,773 names, ordered by most separate stretches first.