Cool resource: On-Line Encyclopedia of Integer Sequences
February 5, 2011
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The On-Line Encyclopedia of Integer Sequences is a very handy, and geek-cool resource. I was looking for a way to calculate triangular numbers, and with this little gem I just searched for the number sequence, and up pops the math, complete with history and examples.
The sequence 0, 1, 3, 6, 10, 15, 21, 28…n, can be calculated as finding the sequence number a with a(n)=n(n+1)/2.
Probably one of the most geek-worthy posts I’ve made anywhere, but I don’t think I would have found the equations that quickly any other way.
Oh, and why did I need that formula? Becuase the Ars Magica role playing game uses the Triangular sequence for the experience point cost for purchasing skills and abilities. It is a nice sequence which starts low, steadily increases in size without including massive leaps, like you’d get using Fibonacci numbers. The Fibonacci numbers ramp-up far too quickly to have a use in skill point purchases (imho).
Yes somehow everything comes back to roleplaying. You get used to it after a while. Stop laughing.