If I’ve got a sequence of numbers from some cultural or physical domain, can I submit it for consideration?
Yes. Anyone who registers and gives a real name can submit sequences. We have thousands of people submitting from all over the world.
This parallels the making of the Oxford English Dictionary chronicled in Simon Winchester’s book The Professor and the Madman, where people all over the planet contributed word entries that were vetted by professional philologists. What kinds of people submit integer sequences?
There’s a wide spectrum: mathematicians, and also a lot of computer scientists who are typically counting the number of steps needed to carry out some sort of procedure, such as sorting a long list of words. The study of the complexity of various algorithms is a major part of computer science and these studies tend to come up with sequences of numbers. For example, if you’ve got a particular sorting algorithm—say you want to arrange playing cards in ascending order—what’s the worst-case number of steps it would take if you have to sort five cards, six cards, seven cards, and so on. There are also people who aren’t mathematicians, but may be professionals in some other field, who send in sequences they’ve come across in their work. And then there are a lot of amateurs.
Mathematics as a field encompasses a great deal of play. One thinks of Martin Gardner’s wildly popular “Mathematical Games” column in Scientific American. I’m fascinated by the notion of amateurs sitting around dreaming up number sequences.
We don’t want to encourage too much of that, but you know, a small amount of dreaming is fine. There are some people who try to get as many sequences as they can into the OEIS; they submit far too much stuff of marginal value. Let’s take the prime numbers. You can ask: “What are all the prime numbers that begin with 7?” Okay, that’s a sequence in the database. But then you could say, “What about all the prime numbers that begin with 763?” That’s obviously too contrived. But if you say, “What about all the prime numbers that contain 666, the ‘number of the beast’?” That’s in the database; they’re called “beastly primes.” Then you recall how when everyone had a fax machine, the fax number was often the one following the phone number. So if my phone number was 555-4440, then my fax would be 555-4441. Well, there was a discussion about including prime numbers that contain 667, the “fax number of the beast.” This is an example of going too far.
So the fax numbers of the beast aren’t in?
I don’t think so. Let me look this up while we’re talking. I can check them by name. Actually, the fax numbers of the beast are in. I sent in the sequence myself.
Your standards have risen since then?
They go up and down. I get so many sequences. Until about 2009, I had to process everything myself. I processed the first 180,000 sequences. Since then, it’s been a wiki and the editors do most of the work. I get called in to resolve disputes and have the final say.
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