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I am interested in downloading the first 25 integers of each sequence in the OEIS database. My reason for wanting to do so is to find the arithmetic mean of the first integers, the arithmetic mean of the second integers, etc. and then plot these values. The hope is that there is a relatively smooth curve that emerges for the mean values even though many of these sequences are wildly chaotic. Similarly I want to find the median, standard deviations, geometric mean and other statistics on these integers. In fact by rounding these values to integers, it would define a new sequence, call it the "OEIS mean 2018 sequence" and so forth. Over time the OEIS sequence would change as more sequences are added to the database, hence the date stamp.

When I visit the site, I can only download one sequence at a time, which would be way too much effort for all 250,000 (+) sequences. Is there a way to query the entire database at once?

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closed as off-topic by Martin R, user223391, Cameron Williams, max_zorn, Namaste Jul 12 '18 at 11:44

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question is not about mathematics, within the scope defined in the help center." – Martin R, Community, Cameron Williams, max_zorn, Namaste
If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ I suggest you to try to find any evidence that "there is a relatively smooth curve" before trying this empirical approach. You know, "extraordinary claims require extraordinary evidence". $\endgroup$ – rafa11111 Jul 12 '18 at 3:46
  • $\begingroup$ Do you mean this page: oeis.org/A000001 ? $\endgroup$ – IronEagle Jul 12 '18 at 3:47
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    $\begingroup$ Have you tried contacting Sloane? $\endgroup$ – Hagen von Eitzen Jul 12 '18 at 3:50
  • $\begingroup$ I might give that a try. I was hoping there was an obvious answer before I tried that. Thanks. $\endgroup$ – PMay Jul 12 '18 at 3:53
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    $\begingroup$ Software-wise, downloading using something like wget with a generated list of all 360,000 urls would take about 4 months run 24/7 at "polite" speeds. I would second contacting the president of OEIS (info is on the main page) or maybe sending an email to webmaster(at)oeis.org. If you're polite, the webmaster might be able to query a database and get you the exact info you need. $\endgroup$ – IronEagle Jul 12 '18 at 3:55
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Yes, you can download the sequences and their A-numbers in a gzipped file that's updated daily.

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  • $\begingroup$ You just saved me a lot of scraping! $\endgroup$ – James Shapiro Mar 7 at 17:46

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