Slashdot Mirror
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."
COMMENTS a(5) reduced by 1 because of a takedown order by the IOC for their trademarked 5-ring configuration.
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.
http://alternatives.rzero.com/
Who are these "many"? Horrible journalism.
OEIS is great. I started working on a project and was able to find some other work done on the same sequence(s)... ,3,5,9,7,15,11,27,... -- my project concerns representing the positive integers in terms of their prime factorization and then examining the properties of various operations on this representation. =)
--TheOrangeSquid Is it any wonder things seem so awry? We swim in a sea of confusion and don't have to think to survive
Maybe it's because i also speak french (but neither english nor french are my native language), but connoisseur.... wtf. When i first heard it used in Futurama, i actually thought it was a small joke of an english speaker completely mispronouncing a french (connaisseur) word, trying to sound smarter than he was, but it's an actual english word 0_0. I cringe every time i hear or read it.
They are numbers. Big ones. Small ones. Numbers that repeat themselves into bigger numbers. Number with zeroes and numbers with ones. Numbers for young and old. Many, many numbers!
Password numbers and briefcase numbers. Hot date and credit card collection numbers. Your weight last year and your weight now :-( numbers.
Your salary number and your worth number. Your debt number and your empty pocket number.
How much you will inherit and how much you actually got.
And so on.
I would have thought it was obvious who they were.
I come here for the love
Encyclopedia of Numbers
If Neil Sloane is so smart, why ain't he rich?
Let me know when his list includes the number sequence for tomorrow's Lotto.
You are welcome on my lawn.
There was the HandBOOK of Integer Sequences. :)
Some of my math professors are probably still wondering how I solved those extra credit problems
It was good for party tricks are well, at the right sort of party obviously.
-jon
I like the sequence: 1,2,1,1,1,1 ...
The X axis is the number of people in an elevator.
The Y axis is how many people know which one farted.
A dingo ate my sig...
1 - 2 - 3 - 4 - 5, which is commonly used for luggage combinations and planetary shields?
When the kids bring home problems that say "What's the next number in this sequence, ..." they can just plug in the numbers and voila.
... as a practice exercise for optimization.
Mike Acton gave an excellent talk Code Clinic 2015: How to Write Code the Compiler Can Actually Optimize where he picked an integer sequence to optimize the run-time to calculate the sequence. Techniques include: memoization, and common sub-term recognition. For 20 values pre-optimization time was: 31 seconds, post-optimization time was: 0.01 seconds.
* https://youtu.be/GPpD4BBtA1Y?t...
Original GDC Talk
* http://gdcvault.com/play/10218...
A095236 is about pay phones, but in the modern era, it is something that males could relate to when choosing a urinal.
Any of you old timers remember the Chemical Rubber Handbook? It's a site now also:
http://www.hbcpnetbase.com/
I admit I've always heard it called the CRC Handbook(s). The "original" being their Chemistry and Physics one (the one at the link), though CRC Press does tons of technical, scientific printing in the US, they also have handbooks on topics in computer science, computer security and many others.
And my copy is I think 80-something-th edition.
Number of arrangements of n circles in the affine plane:
1, 1, 3, 14, 168, ...
If anyone cares, the next number in this sequence is 3172. And no, I did not brute force it, I examined the problem symmetry.
AUTOMATIC LEAD TOOLS IS BEST FOR BUSINESS
Actually, most tools have to be made from harder metals than lead.
Also, don't forget to ask for Jenny for our special discount. 867 5309!
Automatic lead tools are de facto banned in the US unless you're rich. That said, they work just fine without using a harder metal, though I hear DU is in style some places.
Ugh, I actually worked with LeadTools at work a few years ago, it was a pain. We had to rip out all the calls to a previous imaging library because they'd changed their licensing terms to one upper management didn't like... then after I'd replaced everything with calls to LeadTools, it came down that upper management didn't like their terms anyway, and we were going to end up building our own. Which was fine by me, anyway, LeadTools' API is kinda mediocre.
Not sure what that has to do with working from home, though.