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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."
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
Encyclopedia of Numbers
Actually "connoisseur" was the correct French spelling when English borrowed it, and later the French spelling was changed. Racemaniac should study his native language a little bit more before pointing fingers.
That was actually the correct French spelling at the time when it was borrowed into the English language.
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
He didn't even say what his native language is, so we can hardly know if studying it would help his French.
You do realize that the French language has changed the spelling of many of its words over the centuries? Glancing through the online dictionaries, it appears the word "connoisseur" entered the English language around the beginning of the 18th century, 300 years ago. And there's some French words that came over with William the Conqueror almost a millennium ago.
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?
... 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...
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.
He didn't even say what his native language is, so we can hardly know if studying it would help his French.
He did say what it wasn't - "(but neither english nor french are my native language)". So presumably it would help his French only if it were sufficiently closely related to French.
AUTOMATIC LEAD TOOLS IS BEST FOR BUSINESS
Actually, most tools have to be made from harder metals than lead.
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.
Yes, I was attempting to sarcastically point out that the poster's criticism was based on misunderstanding what he was criticizing.