How many votes are needed to undelete?
Whenever I've checked undelete votes required, it always appears to be three. To check, find any deleted question with undelete votes, read the tooltip for the number next to the undelete button. Are undelete votes not scaled similarly to delete votes?
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This currently has a score (sum of question and answers, including negative answers) of +181. At 20:1 that's 9 extra votes, plus the original 3 means 12 to delete. Yet just 3 undelete votes are required to reverse that decision.
Should the number of undelete votes necessary be somewhere between the number of delete votes, to half that?
For example, should 6 votes be required for that question? or 9? or the same count of 12? Less undelete votes than delete votes makes sense, in a way.
That question is perhaps a poor example. It was actually deleted at 11 votes, but the last was a moderator. It also had 9 months to accumulate votes and is in that class of programmer-but-not-programming questions that attracts so much attention on SO. OTGH, that it did attract so much attention and still was closed, stayed closed for a long time as off-topic, and yet was finally deleted, may make it a great example.