Fibonacci elegance sought for $F_{f (n)} + F_{f(n)-1}$Solving Fibonaccis Term Using Golden Ratio...

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Fibonacci elegance sought for $F_{f (n)} + F_{f(n)-1}$


Solving Fibonaccis Term Using Golden Ratio ConverganceFibonacci nth termNeed formula for sequence related to Lucas/Fibonacci numbersFibonacci numbers and golden ratio: $Phi = lim sqrt[n]{F_n}$How is the Binet's formula for Fibonacci reversed in order to find the index for a given Fibonacci number?Fibonacci-related sumHow does one arrive at a certain expression for the Fibonacci Zeta function?Solve for n in golden ratio fibonacci equationWhat is the connection and the difference between the Golden Ratio and Fibonacci Sequence?Powers of the golden ratio













4












$begingroup$


Updated on Friday 15th March 2019 at 5 pm in the light of comments received over the last 24 hours.



The original question was; given the well known variation of Binet's Formula:
$$F_n = frac{phi^n - (-phi)^{-n}}{sqrt{5}}$$



Derive an elegant expression, should one exist, for;
$$F_{log (n)} + F_{log(n)-1}$$



Of course,
$$phi=frac{1+sqrt{5}}{2}$$



Wolfgang Kais has pointed out that this is going to run into technical issues with raising negative numbers to the power of $log(n)$.



Consequently, initially at least, I've been looking instead at
$$F_{f(n)} + F_{f(n)-1}$$
where the function $f$ is sufficiently well behaved to not run into such issues.



In this case,



$$ (sqrt{5})(F_{f(n)} + F_{f(n)-1})=phi^{f(n)}-(-phi)^{-f(n)}+ phi^{f(n)-1}-(-phi)^{-(f(n)-1)}$$
Using the two equivalent facts that
$$1-phi=- frac{1}{phi} :or: phi=1+frac{1}{phi}$$



I proceeded as follows;



$$ (sqrt{5})(F_{f(n)} + F_{f(n)-1})=phi^{f(n)}-big(-frac{1}{phi}big)^{f(n)}+ phi^{f(n)} times phi^{-1}-big(-frac{1}{phi}big)^{(f(n)-1)}$$



$$ =phi^{f(n)}-(1-phi)^{f(n)}+ frac{phi^{f(n)}}{phi}-big(-frac{1}{phi}big)^{f(n)} times big(-frac{1}{phi}big)^{-1}$$



$$ =phi^{f(n)}big(1+frac{1}{phi}big)-(1-phi)^{f(n)}-(1-phi)^{f(n)} times (-phi)$$
$$ =phi times phi^{f(n)} - (1-phi) times (1-phi)^{f(n)}$$



Wolfgang Kais suggested immediately starting with the Fibonacci recurrence relation
$$F_m=F_{m-1}+F_{m-2}$$
from which I deduce that
$$F_{f(n)}+F_{f(n)-1}=F_{f(n)+1}$$
Now, applying the variation on Binet's Formula,
$$F_{f(n)+1} = frac{phi^{f(n)+1} - (-phi)^{-(f(n)+1)}}{sqrt{5}}$$



$$(sqrt{5})(F_{f(n)+1}) = phi times phi^{f(n)} - big(-frac{1}{phi}big)^{f(n)+1}$$
$$ = phi times phi^{f(n)} - (1-phi)^{f(n)+1}$$
$$ =phi times phi^{f(n)} - (1-phi) times (1-phi)^{f(n)}$$



which is the same result as obtained previously which, if nothing else, shows that the variation on Binet's formula satisfies the Fibonacci Recurrence relation.



I'm curious to know if
$$ F_{f(n)+1} = frac{phi times phi^{f(n)}}{sqrt{5}} - frac{(1-phi) times (1-phi)^{f(n)}}{sqrt{5}}$$
is of any use, and is it the best that can be done ?



Possibly I've exhausted what can usefully be done with this question, as I can't see the point of introducing the $log(n)$ function, given the technical hurdles it immediately throws up.



However, any further thoughts are most welcome.



The question originally came from a friend yesterday.



The earlier ask is here : how can i place then values = F(logn)+F(logn-1) in golden ratio Fibonacci series?lognflogn-1-in-golden-ratio-fibonacci-series










share|cite|improve this question











$endgroup$








  • 1




    $begingroup$
    Note the same basic question was asked about $2$ hours earlier at how can i place then values = F(logn)+F(logn-1) in golden ratio Fibonacci series?. I appreciate you leaving a comment on the other question about you asking it here, but you should also mention that somewhere in this new question. Thanks.
    $endgroup$
    – John Omielan
    Mar 14 at 22:28








  • 2




    $begingroup$
    As you can't take a negative number to a non-integer power, $log(n)$ will have to be an integer, and so $F_{log (n)} + F_{log(n)-1} = F_{log(n)+1}$.
    $endgroup$
    – Wolfgang Kais
    Mar 15 at 0:28






  • 1




    $begingroup$
    @Wolfgang Kais : Of course ! And if I use that in the Binet formula I can get to $$F_{log (n)} + F_{log(n)-1} = frac{ phi times phi^{log (n)}-(1-phi) times (1- phi)^{log(n)}}{sqrt{5}}$$ which is so similar to the expression I mention in my question that I think I have a single minus sign error and so have $phi^2$ instead of $(1 - phi)$. I'll try to reconcile the two methods tomorrow. Thanks !
    $endgroup$
    – Martin Hansen
    Mar 15 at 1:21








  • 1




    $begingroup$
    You can also try and use the identity $$x^{log a}=a^{log x}.$$ Unfortunately that requires careful interpretation of complex powers unless $a$ and $x$ are both positive real numbers. It does give you a simple estimate for the sum.
    $endgroup$
    – Jyrki Lahtonen
    Mar 15 at 8:16






  • 1




    $begingroup$
    @MartinHansen: $1-phi$ is also negative. How will you define $(-1)^{log 2}$?
    $endgroup$
    – Wolfgang Kais
    Mar 15 at 8:56


















4












$begingroup$


Updated on Friday 15th March 2019 at 5 pm in the light of comments received over the last 24 hours.



The original question was; given the well known variation of Binet's Formula:
$$F_n = frac{phi^n - (-phi)^{-n}}{sqrt{5}}$$



Derive an elegant expression, should one exist, for;
$$F_{log (n)} + F_{log(n)-1}$$



Of course,
$$phi=frac{1+sqrt{5}}{2}$$



Wolfgang Kais has pointed out that this is going to run into technical issues with raising negative numbers to the power of $log(n)$.



Consequently, initially at least, I've been looking instead at
$$F_{f(n)} + F_{f(n)-1}$$
where the function $f$ is sufficiently well behaved to not run into such issues.



In this case,



$$ (sqrt{5})(F_{f(n)} + F_{f(n)-1})=phi^{f(n)}-(-phi)^{-f(n)}+ phi^{f(n)-1}-(-phi)^{-(f(n)-1)}$$
Using the two equivalent facts that
$$1-phi=- frac{1}{phi} :or: phi=1+frac{1}{phi}$$



I proceeded as follows;



$$ (sqrt{5})(F_{f(n)} + F_{f(n)-1})=phi^{f(n)}-big(-frac{1}{phi}big)^{f(n)}+ phi^{f(n)} times phi^{-1}-big(-frac{1}{phi}big)^{(f(n)-1)}$$



$$ =phi^{f(n)}-(1-phi)^{f(n)}+ frac{phi^{f(n)}}{phi}-big(-frac{1}{phi}big)^{f(n)} times big(-frac{1}{phi}big)^{-1}$$



$$ =phi^{f(n)}big(1+frac{1}{phi}big)-(1-phi)^{f(n)}-(1-phi)^{f(n)} times (-phi)$$
$$ =phi times phi^{f(n)} - (1-phi) times (1-phi)^{f(n)}$$



Wolfgang Kais suggested immediately starting with the Fibonacci recurrence relation
$$F_m=F_{m-1}+F_{m-2}$$
from which I deduce that
$$F_{f(n)}+F_{f(n)-1}=F_{f(n)+1}$$
Now, applying the variation on Binet's Formula,
$$F_{f(n)+1} = frac{phi^{f(n)+1} - (-phi)^{-(f(n)+1)}}{sqrt{5}}$$



$$(sqrt{5})(F_{f(n)+1}) = phi times phi^{f(n)} - big(-frac{1}{phi}big)^{f(n)+1}$$
$$ = phi times phi^{f(n)} - (1-phi)^{f(n)+1}$$
$$ =phi times phi^{f(n)} - (1-phi) times (1-phi)^{f(n)}$$



which is the same result as obtained previously which, if nothing else, shows that the variation on Binet's formula satisfies the Fibonacci Recurrence relation.



I'm curious to know if
$$ F_{f(n)+1} = frac{phi times phi^{f(n)}}{sqrt{5}} - frac{(1-phi) times (1-phi)^{f(n)}}{sqrt{5}}$$
is of any use, and is it the best that can be done ?



Possibly I've exhausted what can usefully be done with this question, as I can't see the point of introducing the $log(n)$ function, given the technical hurdles it immediately throws up.



However, any further thoughts are most welcome.



The question originally came from a friend yesterday.



The earlier ask is here : how can i place then values = F(logn)+F(logn-1) in golden ratio Fibonacci series?lognflogn-1-in-golden-ratio-fibonacci-series










share|cite|improve this question











$endgroup$








  • 1




    $begingroup$
    Note the same basic question was asked about $2$ hours earlier at how can i place then values = F(logn)+F(logn-1) in golden ratio Fibonacci series?. I appreciate you leaving a comment on the other question about you asking it here, but you should also mention that somewhere in this new question. Thanks.
    $endgroup$
    – John Omielan
    Mar 14 at 22:28








  • 2




    $begingroup$
    As you can't take a negative number to a non-integer power, $log(n)$ will have to be an integer, and so $F_{log (n)} + F_{log(n)-1} = F_{log(n)+1}$.
    $endgroup$
    – Wolfgang Kais
    Mar 15 at 0:28






  • 1




    $begingroup$
    @Wolfgang Kais : Of course ! And if I use that in the Binet formula I can get to $$F_{log (n)} + F_{log(n)-1} = frac{ phi times phi^{log (n)}-(1-phi) times (1- phi)^{log(n)}}{sqrt{5}}$$ which is so similar to the expression I mention in my question that I think I have a single minus sign error and so have $phi^2$ instead of $(1 - phi)$. I'll try to reconcile the two methods tomorrow. Thanks !
    $endgroup$
    – Martin Hansen
    Mar 15 at 1:21








  • 1




    $begingroup$
    You can also try and use the identity $$x^{log a}=a^{log x}.$$ Unfortunately that requires careful interpretation of complex powers unless $a$ and $x$ are both positive real numbers. It does give you a simple estimate for the sum.
    $endgroup$
    – Jyrki Lahtonen
    Mar 15 at 8:16






  • 1




    $begingroup$
    @MartinHansen: $1-phi$ is also negative. How will you define $(-1)^{log 2}$?
    $endgroup$
    – Wolfgang Kais
    Mar 15 at 8:56
















4












4








4





$begingroup$


Updated on Friday 15th March 2019 at 5 pm in the light of comments received over the last 24 hours.



The original question was; given the well known variation of Binet's Formula:
$$F_n = frac{phi^n - (-phi)^{-n}}{sqrt{5}}$$



Derive an elegant expression, should one exist, for;
$$F_{log (n)} + F_{log(n)-1}$$



Of course,
$$phi=frac{1+sqrt{5}}{2}$$



Wolfgang Kais has pointed out that this is going to run into technical issues with raising negative numbers to the power of $log(n)$.



Consequently, initially at least, I've been looking instead at
$$F_{f(n)} + F_{f(n)-1}$$
where the function $f$ is sufficiently well behaved to not run into such issues.



In this case,



$$ (sqrt{5})(F_{f(n)} + F_{f(n)-1})=phi^{f(n)}-(-phi)^{-f(n)}+ phi^{f(n)-1}-(-phi)^{-(f(n)-1)}$$
Using the two equivalent facts that
$$1-phi=- frac{1}{phi} :or: phi=1+frac{1}{phi}$$



I proceeded as follows;



$$ (sqrt{5})(F_{f(n)} + F_{f(n)-1})=phi^{f(n)}-big(-frac{1}{phi}big)^{f(n)}+ phi^{f(n)} times phi^{-1}-big(-frac{1}{phi}big)^{(f(n)-1)}$$



$$ =phi^{f(n)}-(1-phi)^{f(n)}+ frac{phi^{f(n)}}{phi}-big(-frac{1}{phi}big)^{f(n)} times big(-frac{1}{phi}big)^{-1}$$



$$ =phi^{f(n)}big(1+frac{1}{phi}big)-(1-phi)^{f(n)}-(1-phi)^{f(n)} times (-phi)$$
$$ =phi times phi^{f(n)} - (1-phi) times (1-phi)^{f(n)}$$



Wolfgang Kais suggested immediately starting with the Fibonacci recurrence relation
$$F_m=F_{m-1}+F_{m-2}$$
from which I deduce that
$$F_{f(n)}+F_{f(n)-1}=F_{f(n)+1}$$
Now, applying the variation on Binet's Formula,
$$F_{f(n)+1} = frac{phi^{f(n)+1} - (-phi)^{-(f(n)+1)}}{sqrt{5}}$$



$$(sqrt{5})(F_{f(n)+1}) = phi times phi^{f(n)} - big(-frac{1}{phi}big)^{f(n)+1}$$
$$ = phi times phi^{f(n)} - (1-phi)^{f(n)+1}$$
$$ =phi times phi^{f(n)} - (1-phi) times (1-phi)^{f(n)}$$



which is the same result as obtained previously which, if nothing else, shows that the variation on Binet's formula satisfies the Fibonacci Recurrence relation.



I'm curious to know if
$$ F_{f(n)+1} = frac{phi times phi^{f(n)}}{sqrt{5}} - frac{(1-phi) times (1-phi)^{f(n)}}{sqrt{5}}$$
is of any use, and is it the best that can be done ?



Possibly I've exhausted what can usefully be done with this question, as I can't see the point of introducing the $log(n)$ function, given the technical hurdles it immediately throws up.



However, any further thoughts are most welcome.



The question originally came from a friend yesterday.



The earlier ask is here : how can i place then values = F(logn)+F(logn-1) in golden ratio Fibonacci series?lognflogn-1-in-golden-ratio-fibonacci-series










share|cite|improve this question











$endgroup$




Updated on Friday 15th March 2019 at 5 pm in the light of comments received over the last 24 hours.



The original question was; given the well known variation of Binet's Formula:
$$F_n = frac{phi^n - (-phi)^{-n}}{sqrt{5}}$$



Derive an elegant expression, should one exist, for;
$$F_{log (n)} + F_{log(n)-1}$$



Of course,
$$phi=frac{1+sqrt{5}}{2}$$



Wolfgang Kais has pointed out that this is going to run into technical issues with raising negative numbers to the power of $log(n)$.



Consequently, initially at least, I've been looking instead at
$$F_{f(n)} + F_{f(n)-1}$$
where the function $f$ is sufficiently well behaved to not run into such issues.



In this case,



$$ (sqrt{5})(F_{f(n)} + F_{f(n)-1})=phi^{f(n)}-(-phi)^{-f(n)}+ phi^{f(n)-1}-(-phi)^{-(f(n)-1)}$$
Using the two equivalent facts that
$$1-phi=- frac{1}{phi} :or: phi=1+frac{1}{phi}$$



I proceeded as follows;



$$ (sqrt{5})(F_{f(n)} + F_{f(n)-1})=phi^{f(n)}-big(-frac{1}{phi}big)^{f(n)}+ phi^{f(n)} times phi^{-1}-big(-frac{1}{phi}big)^{(f(n)-1)}$$



$$ =phi^{f(n)}-(1-phi)^{f(n)}+ frac{phi^{f(n)}}{phi}-big(-frac{1}{phi}big)^{f(n)} times big(-frac{1}{phi}big)^{-1}$$



$$ =phi^{f(n)}big(1+frac{1}{phi}big)-(1-phi)^{f(n)}-(1-phi)^{f(n)} times (-phi)$$
$$ =phi times phi^{f(n)} - (1-phi) times (1-phi)^{f(n)}$$



Wolfgang Kais suggested immediately starting with the Fibonacci recurrence relation
$$F_m=F_{m-1}+F_{m-2}$$
from which I deduce that
$$F_{f(n)}+F_{f(n)-1}=F_{f(n)+1}$$
Now, applying the variation on Binet's Formula,
$$F_{f(n)+1} = frac{phi^{f(n)+1} - (-phi)^{-(f(n)+1)}}{sqrt{5}}$$



$$(sqrt{5})(F_{f(n)+1}) = phi times phi^{f(n)} - big(-frac{1}{phi}big)^{f(n)+1}$$
$$ = phi times phi^{f(n)} - (1-phi)^{f(n)+1}$$
$$ =phi times phi^{f(n)} - (1-phi) times (1-phi)^{f(n)}$$



which is the same result as obtained previously which, if nothing else, shows that the variation on Binet's formula satisfies the Fibonacci Recurrence relation.



I'm curious to know if
$$ F_{f(n)+1} = frac{phi times phi^{f(n)}}{sqrt{5}} - frac{(1-phi) times (1-phi)^{f(n)}}{sqrt{5}}$$
is of any use, and is it the best that can be done ?



Possibly I've exhausted what can usefully be done with this question, as I can't see the point of introducing the $log(n)$ function, given the technical hurdles it immediately throws up.



However, any further thoughts are most welcome.



The question originally came from a friend yesterday.



The earlier ask is here : how can i place then values = F(logn)+F(logn-1) in golden ratio Fibonacci series?lognflogn-1-in-golden-ratio-fibonacci-series







elementary-number-theory fibonacci-numbers golden-ratio






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Mar 15 at 17:22







Martin Hansen

















asked Mar 14 at 22:19









Martin HansenMartin Hansen

707114




707114








  • 1




    $begingroup$
    Note the same basic question was asked about $2$ hours earlier at how can i place then values = F(logn)+F(logn-1) in golden ratio Fibonacci series?. I appreciate you leaving a comment on the other question about you asking it here, but you should also mention that somewhere in this new question. Thanks.
    $endgroup$
    – John Omielan
    Mar 14 at 22:28








  • 2




    $begingroup$
    As you can't take a negative number to a non-integer power, $log(n)$ will have to be an integer, and so $F_{log (n)} + F_{log(n)-1} = F_{log(n)+1}$.
    $endgroup$
    – Wolfgang Kais
    Mar 15 at 0:28






  • 1




    $begingroup$
    @Wolfgang Kais : Of course ! And if I use that in the Binet formula I can get to $$F_{log (n)} + F_{log(n)-1} = frac{ phi times phi^{log (n)}-(1-phi) times (1- phi)^{log(n)}}{sqrt{5}}$$ which is so similar to the expression I mention in my question that I think I have a single minus sign error and so have $phi^2$ instead of $(1 - phi)$. I'll try to reconcile the two methods tomorrow. Thanks !
    $endgroup$
    – Martin Hansen
    Mar 15 at 1:21








  • 1




    $begingroup$
    You can also try and use the identity $$x^{log a}=a^{log x}.$$ Unfortunately that requires careful interpretation of complex powers unless $a$ and $x$ are both positive real numbers. It does give you a simple estimate for the sum.
    $endgroup$
    – Jyrki Lahtonen
    Mar 15 at 8:16






  • 1




    $begingroup$
    @MartinHansen: $1-phi$ is also negative. How will you define $(-1)^{log 2}$?
    $endgroup$
    – Wolfgang Kais
    Mar 15 at 8:56
















  • 1




    $begingroup$
    Note the same basic question was asked about $2$ hours earlier at how can i place then values = F(logn)+F(logn-1) in golden ratio Fibonacci series?. I appreciate you leaving a comment on the other question about you asking it here, but you should also mention that somewhere in this new question. Thanks.
    $endgroup$
    – John Omielan
    Mar 14 at 22:28








  • 2




    $begingroup$
    As you can't take a negative number to a non-integer power, $log(n)$ will have to be an integer, and so $F_{log (n)} + F_{log(n)-1} = F_{log(n)+1}$.
    $endgroup$
    – Wolfgang Kais
    Mar 15 at 0:28






  • 1




    $begingroup$
    @Wolfgang Kais : Of course ! And if I use that in the Binet formula I can get to $$F_{log (n)} + F_{log(n)-1} = frac{ phi times phi^{log (n)}-(1-phi) times (1- phi)^{log(n)}}{sqrt{5}}$$ which is so similar to the expression I mention in my question that I think I have a single minus sign error and so have $phi^2$ instead of $(1 - phi)$. I'll try to reconcile the two methods tomorrow. Thanks !
    $endgroup$
    – Martin Hansen
    Mar 15 at 1:21








  • 1




    $begingroup$
    You can also try and use the identity $$x^{log a}=a^{log x}.$$ Unfortunately that requires careful interpretation of complex powers unless $a$ and $x$ are both positive real numbers. It does give you a simple estimate for the sum.
    $endgroup$
    – Jyrki Lahtonen
    Mar 15 at 8:16






  • 1




    $begingroup$
    @MartinHansen: $1-phi$ is also negative. How will you define $(-1)^{log 2}$?
    $endgroup$
    – Wolfgang Kais
    Mar 15 at 8:56










1




1




$begingroup$
Note the same basic question was asked about $2$ hours earlier at how can i place then values = F(logn)+F(logn-1) in golden ratio Fibonacci series?. I appreciate you leaving a comment on the other question about you asking it here, but you should also mention that somewhere in this new question. Thanks.
$endgroup$
– John Omielan
Mar 14 at 22:28






$begingroup$
Note the same basic question was asked about $2$ hours earlier at how can i place then values = F(logn)+F(logn-1) in golden ratio Fibonacci series?. I appreciate you leaving a comment on the other question about you asking it here, but you should also mention that somewhere in this new question. Thanks.
$endgroup$
– John Omielan
Mar 14 at 22:28






2




2




$begingroup$
As you can't take a negative number to a non-integer power, $log(n)$ will have to be an integer, and so $F_{log (n)} + F_{log(n)-1} = F_{log(n)+1}$.
$endgroup$
– Wolfgang Kais
Mar 15 at 0:28




$begingroup$
As you can't take a negative number to a non-integer power, $log(n)$ will have to be an integer, and so $F_{log (n)} + F_{log(n)-1} = F_{log(n)+1}$.
$endgroup$
– Wolfgang Kais
Mar 15 at 0:28




1




1




$begingroup$
@Wolfgang Kais : Of course ! And if I use that in the Binet formula I can get to $$F_{log (n)} + F_{log(n)-1} = frac{ phi times phi^{log (n)}-(1-phi) times (1- phi)^{log(n)}}{sqrt{5}}$$ which is so similar to the expression I mention in my question that I think I have a single minus sign error and so have $phi^2$ instead of $(1 - phi)$. I'll try to reconcile the two methods tomorrow. Thanks !
$endgroup$
– Martin Hansen
Mar 15 at 1:21






$begingroup$
@Wolfgang Kais : Of course ! And if I use that in the Binet formula I can get to $$F_{log (n)} + F_{log(n)-1} = frac{ phi times phi^{log (n)}-(1-phi) times (1- phi)^{log(n)}}{sqrt{5}}$$ which is so similar to the expression I mention in my question that I think I have a single minus sign error and so have $phi^2$ instead of $(1 - phi)$. I'll try to reconcile the two methods tomorrow. Thanks !
$endgroup$
– Martin Hansen
Mar 15 at 1:21






1




1




$begingroup$
You can also try and use the identity $$x^{log a}=a^{log x}.$$ Unfortunately that requires careful interpretation of complex powers unless $a$ and $x$ are both positive real numbers. It does give you a simple estimate for the sum.
$endgroup$
– Jyrki Lahtonen
Mar 15 at 8:16




$begingroup$
You can also try and use the identity $$x^{log a}=a^{log x}.$$ Unfortunately that requires careful interpretation of complex powers unless $a$ and $x$ are both positive real numbers. It does give you a simple estimate for the sum.
$endgroup$
– Jyrki Lahtonen
Mar 15 at 8:16




1




1




$begingroup$
@MartinHansen: $1-phi$ is also negative. How will you define $(-1)^{log 2}$?
$endgroup$
– Wolfgang Kais
Mar 15 at 8:56






$begingroup$
@MartinHansen: $1-phi$ is also negative. How will you define $(-1)^{log 2}$?
$endgroup$
– Wolfgang Kais
Mar 15 at 8:56












1 Answer
1






active

oldest

votes


















1












$begingroup$

@MartinHansen
Sorry i cant comment as i have reputation less than 50



$$F_{log (n)} + F_{log(n)-1} = frac{ phi^{logn}-(-phi)^{-log(n)}}{sqrt5}+frac{ phi^{log(n)-1}-(-phi)^{-(log(n)-1)}}{sqrt5}$$
$${log (n)} + F_{log(n)-1} = frac{ phi^{log(n)}+(phi)^{(log(n)-1)}}{sqrt5}+frac{ phi^{-log(n)}+(phi)^{-(log(n)-1)}}{sqrt5}$$



as in asymptotic time complexity we tends to ignore constants
$${log (n)} + F_{log(n)-1} = { phi^{log(n)}+(phi)^{(log(n)-1)}}+{phi^{-log(n)}+(phi)^{-(log(n)-1)}}$$
How can i proceed further from here






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    $begingroup$

    @MartinHansen
    Sorry i cant comment as i have reputation less than 50



    $$F_{log (n)} + F_{log(n)-1} = frac{ phi^{logn}-(-phi)^{-log(n)}}{sqrt5}+frac{ phi^{log(n)-1}-(-phi)^{-(log(n)-1)}}{sqrt5}$$
    $${log (n)} + F_{log(n)-1} = frac{ phi^{log(n)}+(phi)^{(log(n)-1)}}{sqrt5}+frac{ phi^{-log(n)}+(phi)^{-(log(n)-1)}}{sqrt5}$$



    as in asymptotic time complexity we tends to ignore constants
    $${log (n)} + F_{log(n)-1} = { phi^{log(n)}+(phi)^{(log(n)-1)}}+{phi^{-log(n)}+(phi)^{-(log(n)-1)}}$$
    How can i proceed further from here






    share|cite|improve this answer









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      1












      $begingroup$

      @MartinHansen
      Sorry i cant comment as i have reputation less than 50



      $$F_{log (n)} + F_{log(n)-1} = frac{ phi^{logn}-(-phi)^{-log(n)}}{sqrt5}+frac{ phi^{log(n)-1}-(-phi)^{-(log(n)-1)}}{sqrt5}$$
      $${log (n)} + F_{log(n)-1} = frac{ phi^{log(n)}+(phi)^{(log(n)-1)}}{sqrt5}+frac{ phi^{-log(n)}+(phi)^{-(log(n)-1)}}{sqrt5}$$



      as in asymptotic time complexity we tends to ignore constants
      $${log (n)} + F_{log(n)-1} = { phi^{log(n)}+(phi)^{(log(n)-1)}}+{phi^{-log(n)}+(phi)^{-(log(n)-1)}}$$
      How can i proceed further from here






      share|cite|improve this answer









      $endgroup$
















        1












        1








        1





        $begingroup$

        @MartinHansen
        Sorry i cant comment as i have reputation less than 50



        $$F_{log (n)} + F_{log(n)-1} = frac{ phi^{logn}-(-phi)^{-log(n)}}{sqrt5}+frac{ phi^{log(n)-1}-(-phi)^{-(log(n)-1)}}{sqrt5}$$
        $${log (n)} + F_{log(n)-1} = frac{ phi^{log(n)}+(phi)^{(log(n)-1)}}{sqrt5}+frac{ phi^{-log(n)}+(phi)^{-(log(n)-1)}}{sqrt5}$$



        as in asymptotic time complexity we tends to ignore constants
        $${log (n)} + F_{log(n)-1} = { phi^{log(n)}+(phi)^{(log(n)-1)}}+{phi^{-log(n)}+(phi)^{-(log(n)-1)}}$$
        How can i proceed further from here






        share|cite|improve this answer









        $endgroup$



        @MartinHansen
        Sorry i cant comment as i have reputation less than 50



        $$F_{log (n)} + F_{log(n)-1} = frac{ phi^{logn}-(-phi)^{-log(n)}}{sqrt5}+frac{ phi^{log(n)-1}-(-phi)^{-(log(n)-1)}}{sqrt5}$$
        $${log (n)} + F_{log(n)-1} = frac{ phi^{log(n)}+(phi)^{(log(n)-1)}}{sqrt5}+frac{ phi^{-log(n)}+(phi)^{-(log(n)-1)}}{sqrt5}$$



        as in asymptotic time complexity we tends to ignore constants
        $${log (n)} + F_{log(n)-1} = { phi^{log(n)}+(phi)^{(log(n)-1)}}+{phi^{-log(n)}+(phi)^{-(log(n)-1)}}$$
        How can i proceed further from here







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Mar 18 at 12:06









        S.OhanzeeS.Ohanzee

        217




        217






























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