
Algebra PreAlgebra and Basic Algebra Math Forum 
 LinkBack  Thread Tools  Display Modes 
April 9th, 2010, 08:56 PM  #1 
Newbie Joined: Nov 2009 Posts: 6 Thanks: 0  Index of a fibonacci number
Given a fibonacci number, is there any efficient way to compute the its position in the sequence ? I found this on Wikipedia [img] http://upload.wikimedia.org/math/4/6/2/ ... ea259e.png [/img] But when F very large (more than 10000 digits) there wont be sufficient precision to get the answer correctly . Is there any way like matrix exponentiation or something that will get me the answer ? PS: if A= [ [0,1],[1,1] ] .. computing A^n (can be done in O(logn)) will give the nth fibonacci number Thank you 
April 10th, 2010, 01:17 PM  #3 
Senior Member Joined: Apr 2008 Posts: 435 Thanks: 0  Re: Index of a fibonacci number
I think you were trying to find the index of the Fibonacci number. Yes, there are a few ways of doing this. Perhaps the easiest way is, 

Tags 
fibonacci, index, number 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
search index  sigma123  Linear Algebra  0  August 7th, 2012 01:53 AM 
Help Please  Index Laws  mikel03  Algebra  1  April 1st, 2009 05:30 AM 
need help determining a value index number  totus  Advanced Statistics  5  March 29th, 2009 08:12 PM 
composite index  jamil  Algebra  0  December 2nd, 2007 04:33 AM 
fibonacci and prime number correlation  soandos  Number Theory  44  November 19th, 2007 12:07 PM 