1:21 AM
@JyrkiLahtonen @Jyrki Speaking of which, did you notice in gimusi's profile a letter from SE staff (Robert Cartaino) pesonally congratulating him for reaching 100K ("Mathematics - You’re killing it (23.10.2019)". He's "killing" it all right, and SE encouragement of such is sending the wrong message.
Perhaps with enough feedback we can discourage SE from sending these emails - which will only complicate the task of nudging such users away from massive duplication.
3

4 hours later…
5:25 AM
@BillDubuque Yes, I noticed it. If I had not resigned earlier, that would have been the last straw. I have been planning to post about this in MSE, because it is also related to Sara Chipps's campaign. I will speak my mind.

10 hours later…
3:29 PM
I guess it takes half a million rep points to know the limit of $(1+\frac1x)^x$ when $x\to\infty$ :-)

Jeebus...
@JyrkiLahtonen Do you feel shame?! Sigh...

2 hours later…
5:20 PM
@JyrkiLahtonen But it doesn't take half a million to delete it. So why not? There is surely nothing novel in any of the answers so deletion is best for site organization. Only if that is consistently done is there any hope of conquering such gamification insprired mass duplication.
2

@JyrkiLahtonen Approach0 is by no means part of MSE and I don't believe it is any one's responsibility to know about it, let alone use it. Unless it is officially in the Help Center like the meta post of How to Ask a good question., and we make this useful known by more people, a few downvotes or comments are not going to work effectively I'm afraid.

@JyrkiLahtonen Update: the question was just gold-badge reopened by gimusi (user). That's an abuse of a gold badge in my opinion (lacking any persuasive argument to do so). Will SE be congratulating him on that too?
3

6:23 PM
@JyrkiLahtonen Btw, it's worth emphasizing that downvoting negative the answers of high-rep users picking cherries in dupes will not have the desired effect. Indeed, all those answers have by now gotten many "pity upvotes" so they now have probably twice the score that they would have normally had. The problem with "pity upvotes" has been around since the dawn of the site..

6:42 PM
@Jack IMNSHO a user with 100k rep should know that that particular question has been covered from every possible angle many times over. Approach0 is there only to make their task of finding dupes easier. Of course, we also maintain (but not well enough) a list of commonly asked questions in meta. For some cases that works better than Approach0 (which shines when you only need a formula).
@BillDubuque That is a fair point with tactical merit. Alas, I am too emotional to keep it in mind, when a red flag is waved in front of my nose.
It may be better to pick close reasons other than duplicate to thwart dupehammer abuse.

6:59 PM
[ SmokeDetector | MS ] Few unique characters in answer, no whitespace in answer, repeating characters in answer (263): Recurrence relation for a differential equation by user726291 on math.SE

7:11 PM
Thanks @Bill. Looks like we got a bit of help from a diamond bearer.
All, I'm sad to say that the rules on deletion are not entirely clear to me. Does downvoting the answers make it easier to delete? Or is that just for Roomba?

8:06 PM
@JyrkiLahtonen "Approach0 is there only to make their task of finding dupes easier." Very true. That's why I said we should put more efforts in making this useful tool known by more people. Putting in comments seems not effective, isn't it. So far, it one makes a poll on meta, I doubt that even for most 100K users, they know what Approach0 is.

2 hours later…
10:04 PM
@JyrkiLahtonen The number of delete votes required to delete a topic is a function of the voting in that topic (votes on the question and its answers). I cannot find anything which makes this function explicit, but, basically, the more upvotes, the harder to delete.
For Roomba, any accepted answer or answer with positive score will prevent deletion, and Roomba won't delete questions which have been closed as duplicate.
@Jack A more fundamental issue is that many of the high XP users don't participate in meta. They don't really know what META is, let along Approach0.

10:23 PM
@XanderHenderson I don't think participating in meta is a must for MSE users, is it? I didn't notice Martin's How to Search meta post (that mentions Approach0) until very recently. Maybe that useful post (which currently has very low views) could be added into the guideline of the site: math.stackexchange.com/help/how-to-ask , which currently only links to the site search engine.

1 hour later…
11:41 PM
Delete: DA, DB, DC, DD, DE, DF, DG, DH

11:52 PM
Delete: DI, DJ, DK, DL, DM, DN, DO, DP