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The Connoisseur of Number Sequences
An anonymous reader writes: 75-year-old Neil Sloane is considered by many to be one of the most influential mathematicians of our time, not because of the theorems he's proved, but because of his creation: The Online Encyclopedia of Integer Sequences (OEIS). Quanta Magazine reports: "This giant repository, which celebrated its 50th anniversary last year, contains more than a quarter of a million different sequences of numbers that arise in different mathematical contexts, such as the prime numbers (2, 3, 5, 7, 11 ) or the Fibonacci sequence (0, 1, 1, 2, 3, 5, 8, 13 ). What's the greatest number of cake slices that can be made with n cuts? Look up sequence A000125 in the OEIS. How many chess positions can be created in n moves? That's sequence A048987. The number of ways to arrange n circles in a plane, with only two crossing at any given point, is A250001. That sequence just joined the collection a few months ago. So far, only its first four terms are known; if you can figure out the fifth, Sloane will want to hear from you."
If you're wondering how an "on-line" collection celebrated its 50th anniversary recently: the collection was begun in 1964; it was made available via the Internet starting in 1996.
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Mathematicians. I don't how many times I've seen a sequence of integers and then gone to Sloane's encyclopedia to see if the sequence is known. This is helpful in both not duplicating others work (e.g. finding out that something one has found is already known) or b) identifying that a given sequence is a known sequence and then using that as a guideline on what to prove. That last bit happens surprisingly often when one has combinatorial structure to something: pop the sequence of numbers you've got into his database and it will tell you something like the first 6 terms matching some nice combinatorial thing and then you can with that guidance go and prove that in general that's what the sequence really is.
Who are these "many"? Horrible journalism.
Unsurprisingly, mathematicians. Many mathematicians use the OEIS frequently, heck experts and professionals from other disciplines like Computer Science, Economics, or Physics routinely use OEIS to identify numeric sequences or patterns.
I'd hazard to say anyone who calls themselves a mathematician has used OEIS (or the book version) at least once. In fact I'd be surprised if you could find anyone with a graduate degree in mathematics who doesn't know who Neil Sloane or OEIS are.
Yes, it is that important.