Re: What is the greatest known Fibonacci number?
- To: mathgroup at smc.vnet.net
- Subject: [mg16655] Re: What is the greatest known Fibonacci number?
- From: Vesa-Matti Sarenius <sarenius at student.oulu.fi>
- Date: Fri, 19 Mar 1999 12:54:05 -0500
- Organization: University of Oulu
- References: <7c5a5k$7op@smc.vnet.net> <7cq3oj$54i@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
> There is an implcit formula for calculating the n'th fibonacci number.
> if you mail pewei at algonet.se I think I have it somewhere.
with Mathematica MatrixPower, you can get large Fibonacci numbers fast.
fibona[n_]:=MatrixPower[{{1,1},{1,0}},n][[1,1]]
In: Timing[fibona[100000]]
Out: {2.38 Second,42026927029951543...}
On Pentium 120...
Roman Maeders book The Mathematrica Programmer discusses more about
making this algorithm more effective.
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