Is the Series 2,3,5,8,13,21 a Fibonacci Sequence?

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Is the series of numbers 2,3,5,8,13,21 ... a fibronacci sequence ? Because it doesn't start with 1 , but it fulfills the explicit formula .
 
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Ling Min Hao said:
Is the series of numbers 2,3,5,8,13,21 ... a fibronacci sequence ? Because it doesn't start with 1 , but it fulfills the explicit formula .
How do you define a Fibonacci sequence?
 
PeroK said:
How do you define a Fibonacci sequence?
I don't know , but from wikipedia , it says Fibronacci starts from either 0,1 or 1,1 but is 2,3,5,8,13,21... a Fibronacci sequence it remains unknown for me ..
 
Ling Min Hao said:
I don't know , but from wikipedia , it says Fibonacci starts from either 0,1 or 1,1 but is 2,3,5,8,13,21... a Fibronacci sequence it remains unknown for me ..
I guess it depends on author and purpose whether only the classical sequence is meant or all possible. I looked up "generalized Fibonacci sequence" and found, e.g. http://www.maths.surrey.ac.uk/hosted-sites/R.Knott/Fibonacci/fibGen.html

As so often the key lies in the question: What's your goal? Usually "a Fibonacci sequence" simply has to obey ##F_{n+1} = F_n + F_{n-1}##. Initial values result in different sequences. If someone speaks about "the Fibonacci sequence ##F_n##" he probably means the one starting with ##(0,1)##. Generalized ones should clearly by stated as such, which often can be recognized the way they define the initial values: ##(F_0,F_1)=(a_0,a_1)## indicates the usage of generalized ones. Formulas which contain ##F_n## without any further explanation probably refer to the classic sequence only.
 
Ling Min Hao said:
I don't know , but from wikipedia , it says Fibronacci starts from either 0,1 or 1,1 but is 2,3,5,8,13,21... a Fibronacci sequence it remains unknown for me ..
A question like this is entirely definition dependent. If you allow a Fibonacci sequence to have any two initial terms, then it is. If not, then it's not. Or, in this case, it is simply not the full sequence.
 
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If you apply prime numbers than it can be consider as a Fibonacci series. If you have any doubts to calculate Fibonacci series than you can visit Ashbox to use calculation tools.