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There are a couple of errors I noticed. When the author says:

Even if we start with two numbers that are completely unrelated in the Fibonacci sequence – say, 8 and 41 – the simple way that we pick the next number of the Fibonacci sequence will cause us to approximate the golden ratio after only a few iterations:

  8 / 41 = 0.1951219
  (8 + 41 = 49) / 8 = 6.125
  (49 + 8 = 57) / 49 = 1.16326531
  (57 + 49 = 106) / 57 = 1.85964912
  (106 + 57 = 163) / 106 = 1.53773585
Why is that? Well, because of the definition of the golden ratio.

He mis-adds in the third step 8+41 ought to be 41+49..

But that's not all. He says "if we start with [any] two numbers...in the Fibonacci sequence" but in fact you can start with ANY two numbers WHETHER OR NOT they are fibonacci numbers.. and perform the Fibonacci operation and divide adjacent numbers and it will converge to the golden ratio. E.g.

  8 
  10 1.25
  18 1.8
  28 1.555555556
  46 1.642857143
  74 1.608695652
  120 1.621621622
  194 1.616666667
  314 1.618556701



The example is showing current=8 previous=41, not current=41 previous=8. I think I did the math right from the those (weird) initial conditions, but maybe not. It converges either way!

Good call on the wording there, though -- changed it from "completely unrelated in the Fibonacci sequence" to "completely unrelated to the Fibonacci sequence" (41 is not a Fibonacci number).


It converges because there is just one error then you do the operation correctly after that.

Your sequence is

  8
  41
  49
  57
  106
  163
What you are looking for is

  8
  41
  49
  90
  139
  229


Yeah, if you swap the initial conditions, you get a different sequence of values. You’re starting with 8 41, but the sequence in the article starts with 41 8.


I see now and also the author acknowledges above. Thanks for clarifying




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