Posted by Jonathan on January 16, 2002, at 21:45:06
In reply to Re: PB social side!!! » Lou Pilder, posted by IsoM on January 16, 2002, at 20:56:19
> I notice there's more women than men here, but perhaps the men are a little shy, or think this is a women's den, or maybe just haven't discovered their nuturing side yet. The men here adds some interesting touches, I'd say! Welcome, Lou!
Here's a male mathematician's answer to Lou's question:
> > > What a group!!! Group people; If yo know the next number in this sequence, let me know. Lou
> > > 1,1,2,3,?
>
> Babbledom people: To clarify the Fibbonacci sequence 1,1,2,3, ? The next number is 5. Now someone tell me the next number in this sequence. Hint: It is not 7.Let's see, 1, 1, 2, 3 and 5 obviously all fit the de Moivre-Binet formula
[(1+r)^n - (1-r)^n] / (r.2^n), where r is the square root of 5,
for n = 1, 2, 3, 4 and 5. I'd guess that substituting n=6 and simplifying should give me the answer you require ... yes, the irrational number r mysteriously disappears like a Cheshire cat, leaving the answer eight :)
If you're over 16 years old < g >, then you may like to disable the parental controls on your web browser and look at a cute Argand diagram of the continuous, complex function described by this formula when n doesn't have to be a whole number. Example for Harry Potter fans: Fibonacci number nine-and-three-quarters is about 48.77 plus a very small multiple of the square root of -1, just enough to shift it off the real axis so that it can't be seen by muggles (as we call those unfortunate ordinary humans who don't share our mathemagical powers):
http://www.mcs.surrey.ac.uk/Personal/R.Knott/Fibonacci/fibFormula.html#binetReal
This is from Ron Knott's excellent web pages on the Fibonacci numbers, which start at
http://www.mcs.surrey.ac.uk/Personal/R.Knott/Fibonacci/fib.html
Welcome to Dr-Bob's Psychomathemagical Babble, Lou.
Jonathan.
poster:Jonathan
thread:16798
URL: http://www.dr-bob.org/babble/social/20020112/msgs/16878.html