Show HN: Twelve Simple Algorithms to Compute Fibonacci Numbers
arxiv.org
arxiv.org
if you have to compute the fib of very large numbers mod n. you can use the fact that the fibonnaci numbers would repeat.( see: https://en.wikipedia.org/wiki/Pisano_period)
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this allows you to solve problems like this: https://www.spoj.com/problems/FIBHARD/
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