Problem 2982. Get a Fibonacci number's index.

Created by Jared Metzel

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Last Solution submitted on Mar 14, 2023

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Jan Orwat on 13 Mar 2015

5.731478440138172e+20 from 7th test is not a Fibonacci Number. 100th Fibonacci Number in proposed convention is 573147844013817084101 which has 21 digits and exceeds double precision.

Rafael S.T. Vieira on 23 Sep 2020

I agree with Jan. http://www.maths.surrey.ac.uk/hosted-sites/R.Knott/Fibonacci/fibtable.html (this list begins at 0). The 100th fibonnaci number is 573147844013817084101 (5.731478440138171e+20), and not 5.731478440138172e+20.

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