closed form of $prod_n=1^inftyleft(fracnn+1right)^(-1)^n-1n$Evaluating a trigonometric product $prod_n=1^inftycos^2left(frac1n^2right)$Closed form for the infinite product $prodlimits_k=0^infty left( 1-x^2^k right)$Closed form of infinite product $prodlimits_k=0^infty 2 left(1-fracx^1/2^k+11+x^1/2^k right)$Does $prod_t=1^inftyleft(1-frac11.127^tright)$ converge to a non-zero value?Closed form for $prod_i=2^infty (1 - frac1i!)$How to compute $prod_n=2^infty left(1-frac1n^nright)$?Closed form for the series $sum_k=1^infty (-1)^k ln left( tanh fracpi k x2 right)$Find closed form of Wallis's product type $prod_n=1^inftyleft(prod_k=0^m(n+k)^mchoose k(-1)^kright)^(-1)^n$Finding the closed form of the product $prod_i = 1^infty (1 - 1/q^i) $.Is the product $prod_n=1^inftyleft(fracGamma(n+frac12)sqrtnGamma(n)right)$ convergent?
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closed form of $prod_n=1^inftyleft(fracnn+1right)^(-1)^n-1n$
Evaluating a trigonometric product $prod_n=1^inftycos^2left(frac1n^2right)$Closed form for the infinite product $prodlimits_k=0^infty left( 1-x^2^k right)$Closed form of infinite product $prodlimits_k=0^infty 2 left(1-fracx^1/2^k+11+x^1/2^k right)$Does $prod_t=1^inftyleft(1-frac11.127^tright)$ converge to a non-zero value?Closed form for $prod_i=2^infty (1 - frac1i!)$How to compute $prod_n=2^infty left(1-frac1n^nright)$?Closed form for the series $sum_k=1^infty (-1)^k ln left( tanh fracpi k x2 right)$Find closed form of Wallis's product type $prod_n=1^inftyleft(prod_k=0^m(n+k)^mchoose k(-1)^kright)^(-1)^n$Finding the closed form of the product $prod_i = 1^infty (1 - 1/q^i) $.Is the product $prod_n=1^inftyleft(fracGamma(n+frac12)sqrtnGamma(n)right)$ convergent?
$begingroup$
I am looking for the closed form of this product.
$$prod_n=1^inftyleft(fracnn+1right)^(-1)^n-1n$$
I have sees it somewhere before but I can't remember it closed form. I remember the Glaisher's constant it is invloved alone with $2^7/6$ and maybe e (exponential function constant) also.
Does anyone knows it closed form?
infinite-product
$endgroup$
add a comment |
$begingroup$
I am looking for the closed form of this product.
$$prod_n=1^inftyleft(fracnn+1right)^(-1)^n-1n$$
I have sees it somewhere before but I can't remember it closed form. I remember the Glaisher's constant it is invloved alone with $2^7/6$ and maybe e (exponential function constant) also.
Does anyone knows it closed form?
infinite-product
$endgroup$
$begingroup$
Is it convergent? I got the product to be $$frac 3^5 cdot 5^9 cdot 7^13 cdots 2^3 cdot 4^7 cdot 6^11 cdots$$ which is definitely divergent.
$endgroup$
– Dbchatto67
Mar 14 at 7:32
$begingroup$
There are two limits possible, please see my answer.
$endgroup$
– user90369
Mar 14 at 16:51
add a comment |
$begingroup$
I am looking for the closed form of this product.
$$prod_n=1^inftyleft(fracnn+1right)^(-1)^n-1n$$
I have sees it somewhere before but I can't remember it closed form. I remember the Glaisher's constant it is invloved alone with $2^7/6$ and maybe e (exponential function constant) also.
Does anyone knows it closed form?
infinite-product
$endgroup$
I am looking for the closed form of this product.
$$prod_n=1^inftyleft(fracnn+1right)^(-1)^n-1n$$
I have sees it somewhere before but I can't remember it closed form. I remember the Glaisher's constant it is invloved alone with $2^7/6$ and maybe e (exponential function constant) also.
Does anyone knows it closed form?
infinite-product
infinite-product
asked Mar 14 at 6:56
coffeeecoffeee
14518
14518
$begingroup$
Is it convergent? I got the product to be $$frac 3^5 cdot 5^9 cdot 7^13 cdots 2^3 cdot 4^7 cdot 6^11 cdots$$ which is definitely divergent.
$endgroup$
– Dbchatto67
Mar 14 at 7:32
$begingroup$
There are two limits possible, please see my answer.
$endgroup$
– user90369
Mar 14 at 16:51
add a comment |
$begingroup$
Is it convergent? I got the product to be $$frac 3^5 cdot 5^9 cdot 7^13 cdots 2^3 cdot 4^7 cdot 6^11 cdots$$ which is definitely divergent.
$endgroup$
– Dbchatto67
Mar 14 at 7:32
$begingroup$
There are two limits possible, please see my answer.
$endgroup$
– user90369
Mar 14 at 16:51
$begingroup$
Is it convergent? I got the product to be $$frac 3^5 cdot 5^9 cdot 7^13 cdots 2^3 cdot 4^7 cdot 6^11 cdots$$ which is definitely divergent.
$endgroup$
– Dbchatto67
Mar 14 at 7:32
$begingroup$
Is it convergent? I got the product to be $$frac 3^5 cdot 5^9 cdot 7^13 cdots 2^3 cdot 4^7 cdot 6^11 cdots$$ which is definitely divergent.
$endgroup$
– Dbchatto67
Mar 14 at 7:32
$begingroup$
There are two limits possible, please see my answer.
$endgroup$
– user90369
Mar 14 at 16:51
$begingroup$
There are two limits possible, please see my answer.
$endgroup$
– user90369
Mar 14 at 16:51
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
$displaystyle 1/prodlimits_n=1^2Nleft(fracnn+1right)^(-1)^n-1n = frac1sqrt2 left( frace^N/2N^-1/8 prodlimits_n=1^Nleft(1+frac12nright)^n
right)^4 left( frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n right)^-1 $
$displaystyle limlimits_Ntoinfty frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n = limlimits_Ntoinftyfrace^N N^-1/2 prodlimits_n=1^Nleft(1+frac1nright)^n = fracsqrt2pieenspaceenspace$ (e.g. by the Stirling formula)
The first calculation formula of Glaisher for the constant named after him (but written here more compact with products instead of series) is:
$$A=2^1/36pi^1/6left( limlimits_Ntoinfty frace^N/2N^-1/8 prodlimits_n=1^Nleft(1+frac12nright)^n
right)^2/3left( limlimits_Ntoinfty frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n right)^-1/3$$
(see Glaisher page 46 formula (7))
We potentiate this equation of Glaisher on both sides with 6 and multiply one time the left side with $fracsqrt2pie$ and the right with it’s product. After a few simple elementary conversions follows:
$displaystyle limlimits_Ntoinftyprodlimits_n=1^2Nleft(fracnn+1right)^(-1)^n-1n = 2^1/6pi^1/2eA^-6 approx 1.2157517513…$
$displaystyle limlimits_Ntoinftyprodlimits_n=1^2N+1left(fracnn+1right)^(-1)^n-1n = 2^1/6pi^1/2A^-6 approx 0.44725…$
$endgroup$
$begingroup$
thank you for showing the full answer
$endgroup$
– coffeee
Mar 15 at 20:31
$begingroup$
@coffeee : You are welcome, it was a pleasure. ;)
$endgroup$
– user90369
Mar 15 at 22:26
add a comment |
$begingroup$
Let $$a_n=left(fracnn+1right)^(-1)^n-1 n$$ then
$$a_2p= left(frac2p2 p+1right)^-2 pqquad textandqquad a_2p+1=left(frac2 p+12 p+2right)^2 p+1$$
Now, using a CAS,
$$prod_p=1^m a_2p=fracsqrt[12]2 sqrtpi exp left(-2 zeta ^(1,0)(-1,m+1)+2 zeta
^(1,0)left(-1,m+frac32right)+frac14right)A^3 ,Gamma
left(m+frac32right)$$
$$prod_p=1^m a_2p+1=frac2 sqrt[12]2 Gamma (m+2) exp left(2 zeta
^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac14right)A^3$$
$$b_m=frac 12prod_p=1^m a_2pprod_p=1^m a_2p+1$$ $$b_m=frac2^frac 16sqrtpi Gamma (m+2) exp left(-2 zeta ^(1,0)(-1,m+1)+4
zeta ^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac12right)A^6 ,Gamma left(m+frac32right)$$
$$b_m=frac2^frac 16 sqrtpi , Gamma (m+2)A^4 ,H(m)^2,Gamma
left(m+frac32right)exp left(4 zeta ^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac13right)$$ where appears the hyperfactorial function.
Taking logarithms and using Stirling like approximations and then continuing with Taylor expansions using $b_m=e^log(b_m)$
$$b_m=frac2^frac 16 sqrt piA^6left(1+frac18 m-frac49384 m^2+frac1271024 m^3+Oleft(frac1m^4right) right)$$
$$colorbluelim_mto infty , b_m=frac2^frac 16 sqrt piA^6$$
$endgroup$
$begingroup$
Thank you for the answer @Claude Leibovic
$endgroup$
– coffeee
Mar 14 at 10:16
$begingroup$
@coffeee. You are very welcome ! Using Wolfram Alpha, type product of ((1 + 2*p)/(2 + 2*p))^(1 + 2*p)/(2^(2*p)*(p/(1 + 2*p))^(2*p)) from p=1 to infinity and you will get the result.
$endgroup$
– Claude Leibovici
Mar 14 at 10:22
$begingroup$
@coffeee. Take care : I could be wrong by a factor of two since I used $b_m=prod_p=1^m a_2pprod_p=1^m a_2p+1$ instead of $b_m=prod_p=1^m a_2pprod_p=colorred0^m a_2p+1$. I need to check again tomorrow morning.
$endgroup$
– Claude Leibovici
Mar 14 at 14:42
add a comment |
Your Answer
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2 Answers
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2 Answers
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$begingroup$
$displaystyle 1/prodlimits_n=1^2Nleft(fracnn+1right)^(-1)^n-1n = frac1sqrt2 left( frace^N/2N^-1/8 prodlimits_n=1^Nleft(1+frac12nright)^n
right)^4 left( frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n right)^-1 $
$displaystyle limlimits_Ntoinfty frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n = limlimits_Ntoinftyfrace^N N^-1/2 prodlimits_n=1^Nleft(1+frac1nright)^n = fracsqrt2pieenspaceenspace$ (e.g. by the Stirling formula)
The first calculation formula of Glaisher for the constant named after him (but written here more compact with products instead of series) is:
$$A=2^1/36pi^1/6left( limlimits_Ntoinfty frace^N/2N^-1/8 prodlimits_n=1^Nleft(1+frac12nright)^n
right)^2/3left( limlimits_Ntoinfty frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n right)^-1/3$$
(see Glaisher page 46 formula (7))
We potentiate this equation of Glaisher on both sides with 6 and multiply one time the left side with $fracsqrt2pie$ and the right with it’s product. After a few simple elementary conversions follows:
$displaystyle limlimits_Ntoinftyprodlimits_n=1^2Nleft(fracnn+1right)^(-1)^n-1n = 2^1/6pi^1/2eA^-6 approx 1.2157517513…$
$displaystyle limlimits_Ntoinftyprodlimits_n=1^2N+1left(fracnn+1right)^(-1)^n-1n = 2^1/6pi^1/2A^-6 approx 0.44725…$
$endgroup$
$begingroup$
thank you for showing the full answer
$endgroup$
– coffeee
Mar 15 at 20:31
$begingroup$
@coffeee : You are welcome, it was a pleasure. ;)
$endgroup$
– user90369
Mar 15 at 22:26
add a comment |
$begingroup$
$displaystyle 1/prodlimits_n=1^2Nleft(fracnn+1right)^(-1)^n-1n = frac1sqrt2 left( frace^N/2N^-1/8 prodlimits_n=1^Nleft(1+frac12nright)^n
right)^4 left( frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n right)^-1 $
$displaystyle limlimits_Ntoinfty frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n = limlimits_Ntoinftyfrace^N N^-1/2 prodlimits_n=1^Nleft(1+frac1nright)^n = fracsqrt2pieenspaceenspace$ (e.g. by the Stirling formula)
The first calculation formula of Glaisher for the constant named after him (but written here more compact with products instead of series) is:
$$A=2^1/36pi^1/6left( limlimits_Ntoinfty frace^N/2N^-1/8 prodlimits_n=1^Nleft(1+frac12nright)^n
right)^2/3left( limlimits_Ntoinfty frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n right)^-1/3$$
(see Glaisher page 46 formula (7))
We potentiate this equation of Glaisher on both sides with 6 and multiply one time the left side with $fracsqrt2pie$ and the right with it’s product. After a few simple elementary conversions follows:
$displaystyle limlimits_Ntoinftyprodlimits_n=1^2Nleft(fracnn+1right)^(-1)^n-1n = 2^1/6pi^1/2eA^-6 approx 1.2157517513…$
$displaystyle limlimits_Ntoinftyprodlimits_n=1^2N+1left(fracnn+1right)^(-1)^n-1n = 2^1/6pi^1/2A^-6 approx 0.44725…$
$endgroup$
$begingroup$
thank you for showing the full answer
$endgroup$
– coffeee
Mar 15 at 20:31
$begingroup$
@coffeee : You are welcome, it was a pleasure. ;)
$endgroup$
– user90369
Mar 15 at 22:26
add a comment |
$begingroup$
$displaystyle 1/prodlimits_n=1^2Nleft(fracnn+1right)^(-1)^n-1n = frac1sqrt2 left( frace^N/2N^-1/8 prodlimits_n=1^Nleft(1+frac12nright)^n
right)^4 left( frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n right)^-1 $
$displaystyle limlimits_Ntoinfty frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n = limlimits_Ntoinftyfrace^N N^-1/2 prodlimits_n=1^Nleft(1+frac1nright)^n = fracsqrt2pieenspaceenspace$ (e.g. by the Stirling formula)
The first calculation formula of Glaisher for the constant named after him (but written here more compact with products instead of series) is:
$$A=2^1/36pi^1/6left( limlimits_Ntoinfty frace^N/2N^-1/8 prodlimits_n=1^Nleft(1+frac12nright)^n
right)^2/3left( limlimits_Ntoinfty frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n right)^-1/3$$
(see Glaisher page 46 formula (7))
We potentiate this equation of Glaisher on both sides with 6 and multiply one time the left side with $fracsqrt2pie$ and the right with it’s product. After a few simple elementary conversions follows:
$displaystyle limlimits_Ntoinftyprodlimits_n=1^2Nleft(fracnn+1right)^(-1)^n-1n = 2^1/6pi^1/2eA^-6 approx 1.2157517513…$
$displaystyle limlimits_Ntoinftyprodlimits_n=1^2N+1left(fracnn+1right)^(-1)^n-1n = 2^1/6pi^1/2A^-6 approx 0.44725…$
$endgroup$
$displaystyle 1/prodlimits_n=1^2Nleft(fracnn+1right)^(-1)^n-1n = frac1sqrt2 left( frace^N/2N^-1/8 prodlimits_n=1^Nleft(1+frac12nright)^n
right)^4 left( frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n right)^-1 $
$displaystyle limlimits_Ntoinfty frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n = limlimits_Ntoinftyfrace^N N^-1/2 prodlimits_n=1^Nleft(1+frac1nright)^n = fracsqrt2pieenspaceenspace$ (e.g. by the Stirling formula)
The first calculation formula of Glaisher for the constant named after him (but written here more compact with products instead of series) is:
$$A=2^1/36pi^1/6left( limlimits_Ntoinfty frace^N/2N^-1/8 prodlimits_n=1^Nleft(1+frac12nright)^n
right)^2/3left( limlimits_Ntoinfty frace^2N(2N)^-1/2 prodlimits_n=1^2Nleft(1+frac1nright)^n right)^-1/3$$
(see Glaisher page 46 formula (7))
We potentiate this equation of Glaisher on both sides with 6 and multiply one time the left side with $fracsqrt2pie$ and the right with it’s product. After a few simple elementary conversions follows:
$displaystyle limlimits_Ntoinftyprodlimits_n=1^2Nleft(fracnn+1right)^(-1)^n-1n = 2^1/6pi^1/2eA^-6 approx 1.2157517513…$
$displaystyle limlimits_Ntoinftyprodlimits_n=1^2N+1left(fracnn+1right)^(-1)^n-1n = 2^1/6pi^1/2A^-6 approx 0.44725…$
edited Mar 14 at 18:42
answered Mar 14 at 16:08
user90369user90369
8,475925
8,475925
$begingroup$
thank you for showing the full answer
$endgroup$
– coffeee
Mar 15 at 20:31
$begingroup$
@coffeee : You are welcome, it was a pleasure. ;)
$endgroup$
– user90369
Mar 15 at 22:26
add a comment |
$begingroup$
thank you for showing the full answer
$endgroup$
– coffeee
Mar 15 at 20:31
$begingroup$
@coffeee : You are welcome, it was a pleasure. ;)
$endgroup$
– user90369
Mar 15 at 22:26
$begingroup$
thank you for showing the full answer
$endgroup$
– coffeee
Mar 15 at 20:31
$begingroup$
thank you for showing the full answer
$endgroup$
– coffeee
Mar 15 at 20:31
$begingroup$
@coffeee : You are welcome, it was a pleasure. ;)
$endgroup$
– user90369
Mar 15 at 22:26
$begingroup$
@coffeee : You are welcome, it was a pleasure. ;)
$endgroup$
– user90369
Mar 15 at 22:26
add a comment |
$begingroup$
Let $$a_n=left(fracnn+1right)^(-1)^n-1 n$$ then
$$a_2p= left(frac2p2 p+1right)^-2 pqquad textandqquad a_2p+1=left(frac2 p+12 p+2right)^2 p+1$$
Now, using a CAS,
$$prod_p=1^m a_2p=fracsqrt[12]2 sqrtpi exp left(-2 zeta ^(1,0)(-1,m+1)+2 zeta
^(1,0)left(-1,m+frac32right)+frac14right)A^3 ,Gamma
left(m+frac32right)$$
$$prod_p=1^m a_2p+1=frac2 sqrt[12]2 Gamma (m+2) exp left(2 zeta
^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac14right)A^3$$
$$b_m=frac 12prod_p=1^m a_2pprod_p=1^m a_2p+1$$ $$b_m=frac2^frac 16sqrtpi Gamma (m+2) exp left(-2 zeta ^(1,0)(-1,m+1)+4
zeta ^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac12right)A^6 ,Gamma left(m+frac32right)$$
$$b_m=frac2^frac 16 sqrtpi , Gamma (m+2)A^4 ,H(m)^2,Gamma
left(m+frac32right)exp left(4 zeta ^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac13right)$$ where appears the hyperfactorial function.
Taking logarithms and using Stirling like approximations and then continuing with Taylor expansions using $b_m=e^log(b_m)$
$$b_m=frac2^frac 16 sqrt piA^6left(1+frac18 m-frac49384 m^2+frac1271024 m^3+Oleft(frac1m^4right) right)$$
$$colorbluelim_mto infty , b_m=frac2^frac 16 sqrt piA^6$$
$endgroup$
$begingroup$
Thank you for the answer @Claude Leibovic
$endgroup$
– coffeee
Mar 14 at 10:16
$begingroup$
@coffeee. You are very welcome ! Using Wolfram Alpha, type product of ((1 + 2*p)/(2 + 2*p))^(1 + 2*p)/(2^(2*p)*(p/(1 + 2*p))^(2*p)) from p=1 to infinity and you will get the result.
$endgroup$
– Claude Leibovici
Mar 14 at 10:22
$begingroup$
@coffeee. Take care : I could be wrong by a factor of two since I used $b_m=prod_p=1^m a_2pprod_p=1^m a_2p+1$ instead of $b_m=prod_p=1^m a_2pprod_p=colorred0^m a_2p+1$. I need to check again tomorrow morning.
$endgroup$
– Claude Leibovici
Mar 14 at 14:42
add a comment |
$begingroup$
Let $$a_n=left(fracnn+1right)^(-1)^n-1 n$$ then
$$a_2p= left(frac2p2 p+1right)^-2 pqquad textandqquad a_2p+1=left(frac2 p+12 p+2right)^2 p+1$$
Now, using a CAS,
$$prod_p=1^m a_2p=fracsqrt[12]2 sqrtpi exp left(-2 zeta ^(1,0)(-1,m+1)+2 zeta
^(1,0)left(-1,m+frac32right)+frac14right)A^3 ,Gamma
left(m+frac32right)$$
$$prod_p=1^m a_2p+1=frac2 sqrt[12]2 Gamma (m+2) exp left(2 zeta
^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac14right)A^3$$
$$b_m=frac 12prod_p=1^m a_2pprod_p=1^m a_2p+1$$ $$b_m=frac2^frac 16sqrtpi Gamma (m+2) exp left(-2 zeta ^(1,0)(-1,m+1)+4
zeta ^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac12right)A^6 ,Gamma left(m+frac32right)$$
$$b_m=frac2^frac 16 sqrtpi , Gamma (m+2)A^4 ,H(m)^2,Gamma
left(m+frac32right)exp left(4 zeta ^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac13right)$$ where appears the hyperfactorial function.
Taking logarithms and using Stirling like approximations and then continuing with Taylor expansions using $b_m=e^log(b_m)$
$$b_m=frac2^frac 16 sqrt piA^6left(1+frac18 m-frac49384 m^2+frac1271024 m^3+Oleft(frac1m^4right) right)$$
$$colorbluelim_mto infty , b_m=frac2^frac 16 sqrt piA^6$$
$endgroup$
$begingroup$
Thank you for the answer @Claude Leibovic
$endgroup$
– coffeee
Mar 14 at 10:16
$begingroup$
@coffeee. You are very welcome ! Using Wolfram Alpha, type product of ((1 + 2*p)/(2 + 2*p))^(1 + 2*p)/(2^(2*p)*(p/(1 + 2*p))^(2*p)) from p=1 to infinity and you will get the result.
$endgroup$
– Claude Leibovici
Mar 14 at 10:22
$begingroup$
@coffeee. Take care : I could be wrong by a factor of two since I used $b_m=prod_p=1^m a_2pprod_p=1^m a_2p+1$ instead of $b_m=prod_p=1^m a_2pprod_p=colorred0^m a_2p+1$. I need to check again tomorrow morning.
$endgroup$
– Claude Leibovici
Mar 14 at 14:42
add a comment |
$begingroup$
Let $$a_n=left(fracnn+1right)^(-1)^n-1 n$$ then
$$a_2p= left(frac2p2 p+1right)^-2 pqquad textandqquad a_2p+1=left(frac2 p+12 p+2right)^2 p+1$$
Now, using a CAS,
$$prod_p=1^m a_2p=fracsqrt[12]2 sqrtpi exp left(-2 zeta ^(1,0)(-1,m+1)+2 zeta
^(1,0)left(-1,m+frac32right)+frac14right)A^3 ,Gamma
left(m+frac32right)$$
$$prod_p=1^m a_2p+1=frac2 sqrt[12]2 Gamma (m+2) exp left(2 zeta
^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac14right)A^3$$
$$b_m=frac 12prod_p=1^m a_2pprod_p=1^m a_2p+1$$ $$b_m=frac2^frac 16sqrtpi Gamma (m+2) exp left(-2 zeta ^(1,0)(-1,m+1)+4
zeta ^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac12right)A^6 ,Gamma left(m+frac32right)$$
$$b_m=frac2^frac 16 sqrtpi , Gamma (m+2)A^4 ,H(m)^2,Gamma
left(m+frac32right)exp left(4 zeta ^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac13right)$$ where appears the hyperfactorial function.
Taking logarithms and using Stirling like approximations and then continuing with Taylor expansions using $b_m=e^log(b_m)$
$$b_m=frac2^frac 16 sqrt piA^6left(1+frac18 m-frac49384 m^2+frac1271024 m^3+Oleft(frac1m^4right) right)$$
$$colorbluelim_mto infty , b_m=frac2^frac 16 sqrt piA^6$$
$endgroup$
Let $$a_n=left(fracnn+1right)^(-1)^n-1 n$$ then
$$a_2p= left(frac2p2 p+1right)^-2 pqquad textandqquad a_2p+1=left(frac2 p+12 p+2right)^2 p+1$$
Now, using a CAS,
$$prod_p=1^m a_2p=fracsqrt[12]2 sqrtpi exp left(-2 zeta ^(1,0)(-1,m+1)+2 zeta
^(1,0)left(-1,m+frac32right)+frac14right)A^3 ,Gamma
left(m+frac32right)$$
$$prod_p=1^m a_2p+1=frac2 sqrt[12]2 Gamma (m+2) exp left(2 zeta
^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac14right)A^3$$
$$b_m=frac 12prod_p=1^m a_2pprod_p=1^m a_2p+1$$ $$b_m=frac2^frac 16sqrtpi Gamma (m+2) exp left(-2 zeta ^(1,0)(-1,m+1)+4
zeta ^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac12right)A^6 ,Gamma left(m+frac32right)$$
$$b_m=frac2^frac 16 sqrtpi , Gamma (m+2)A^4 ,H(m)^2,Gamma
left(m+frac32right)exp left(4 zeta ^(1,0)left(-1,m+frac32right)-2 zeta
^(1,0)(-1,m+2)+frac13right)$$ where appears the hyperfactorial function.
Taking logarithms and using Stirling like approximations and then continuing with Taylor expansions using $b_m=e^log(b_m)$
$$b_m=frac2^frac 16 sqrt piA^6left(1+frac18 m-frac49384 m^2+frac1271024 m^3+Oleft(frac1m^4right) right)$$
$$colorbluelim_mto infty , b_m=frac2^frac 16 sqrt piA^6$$
edited Mar 15 at 3:44
answered Mar 14 at 8:43
Claude LeiboviciClaude Leibovici
124k1158135
124k1158135
$begingroup$
Thank you for the answer @Claude Leibovic
$endgroup$
– coffeee
Mar 14 at 10:16
$begingroup$
@coffeee. You are very welcome ! Using Wolfram Alpha, type product of ((1 + 2*p)/(2 + 2*p))^(1 + 2*p)/(2^(2*p)*(p/(1 + 2*p))^(2*p)) from p=1 to infinity and you will get the result.
$endgroup$
– Claude Leibovici
Mar 14 at 10:22
$begingroup$
@coffeee. Take care : I could be wrong by a factor of two since I used $b_m=prod_p=1^m a_2pprod_p=1^m a_2p+1$ instead of $b_m=prod_p=1^m a_2pprod_p=colorred0^m a_2p+1$. I need to check again tomorrow morning.
$endgroup$
– Claude Leibovici
Mar 14 at 14:42
add a comment |
$begingroup$
Thank you for the answer @Claude Leibovic
$endgroup$
– coffeee
Mar 14 at 10:16
$begingroup$
@coffeee. You are very welcome ! Using Wolfram Alpha, type product of ((1 + 2*p)/(2 + 2*p))^(1 + 2*p)/(2^(2*p)*(p/(1 + 2*p))^(2*p)) from p=1 to infinity and you will get the result.
$endgroup$
– Claude Leibovici
Mar 14 at 10:22
$begingroup$
@coffeee. Take care : I could be wrong by a factor of two since I used $b_m=prod_p=1^m a_2pprod_p=1^m a_2p+1$ instead of $b_m=prod_p=1^m a_2pprod_p=colorred0^m a_2p+1$. I need to check again tomorrow morning.
$endgroup$
– Claude Leibovici
Mar 14 at 14:42
$begingroup$
Thank you for the answer @Claude Leibovic
$endgroup$
– coffeee
Mar 14 at 10:16
$begingroup$
Thank you for the answer @Claude Leibovic
$endgroup$
– coffeee
Mar 14 at 10:16
$begingroup$
@coffeee. You are very welcome ! Using Wolfram Alpha, type product of ((1 + 2*p)/(2 + 2*p))^(1 + 2*p)/(2^(2*p)*(p/(1 + 2*p))^(2*p)) from p=1 to infinity and you will get the result.
$endgroup$
– Claude Leibovici
Mar 14 at 10:22
$begingroup$
@coffeee. You are very welcome ! Using Wolfram Alpha, type product of ((1 + 2*p)/(2 + 2*p))^(1 + 2*p)/(2^(2*p)*(p/(1 + 2*p))^(2*p)) from p=1 to infinity and you will get the result.
$endgroup$
– Claude Leibovici
Mar 14 at 10:22
$begingroup$
@coffeee. Take care : I could be wrong by a factor of two since I used $b_m=prod_p=1^m a_2pprod_p=1^m a_2p+1$ instead of $b_m=prod_p=1^m a_2pprod_p=colorred0^m a_2p+1$. I need to check again tomorrow morning.
$endgroup$
– Claude Leibovici
Mar 14 at 14:42
$begingroup$
@coffeee. Take care : I could be wrong by a factor of two since I used $b_m=prod_p=1^m a_2pprod_p=1^m a_2p+1$ instead of $b_m=prod_p=1^m a_2pprod_p=colorred0^m a_2p+1$. I need to check again tomorrow morning.
$endgroup$
– Claude Leibovici
Mar 14 at 14:42
add a comment |
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Is it convergent? I got the product to be $$frac 3^5 cdot 5^9 cdot 7^13 cdots 2^3 cdot 4^7 cdot 6^11 cdots$$ which is definitely divergent.
$endgroup$
– Dbchatto67
Mar 14 at 7:32
$begingroup$
There are two limits possible, please see my answer.
$endgroup$
– user90369
Mar 14 at 16:51