From: rancid moth on
product(k=1..m) Binomial(2k,k)^(8*(2k+1)) = ?
From: rancid moth on

"rancid moth" <rancidmoth(a)yahoo.com> wrote in message
news:i06vf1$2mg$1(a)speranza.aioe.org...
> product(k=1..m) Binomial(2k,k)^(8*(2k+1)) = ?

Actually i think i have it. i believe i can express it in terms of a finite
product of Barnes-G functions. perhaps there is an easier way to obtain it
though?

From: Robert Israel on
"rancid moth" <rancidmoth(a)yahoo.com> writes:

> product(k=1..m) Binomial(2k,k)^(8*(2k+1)) = ?

Well, if p is a prime, by a theorem of Kummer the highest power of p in
binomial(2k,k) is the number of times you "carry 1" in adding k + k in
base p.
If you call that C(k,p), your answer is

product_p p^(8 sum_{k=1}^m (2k+1) C(k,p))

the product being over all primes <= 2m.
--
Robert Israel israel(a)math.MyUniversitysInitials.ca
Department of Mathematics http://www.math.ubc.ca/~israel
University of British Columbia Vancouver, BC, Canada
From: rancid moth on
"Robert Israel" <israel(a)math.MyUniversitysInitials.ca> wrote in message
news:rbisrael.20100627222655$02d7(a)news.acm.uiuc.edu...
> "rancid moth" <rancidmoth(a)yahoo.com> writes:
>
>> product(k=1..m) Binomial(2k,k)^(8*(2k+1)) = ?
>
> Well, if p is a prime, by a theorem of Kummer the highest power of p in
> binomial(2k,k) is the number of times you "carry 1" in adding k + k in
> base p.
> If you call that C(k,p), your answer is
>
> product_p p^(8 sum_{k=1}^m (2k+1) C(k,p))
>
> the product being over all primes <= 2m.
> --
> Robert Israel israel(a)math.MyUniversitysInitials.ca
> Department of Mathematics http://www.math.ubc.ca/~israel
> University of British Columbia Vancouver, BC, Canada

Thank you...that's the kind of thing i was after.

Now I've just got to get my head around it.

cheers



From: Rob Johnson on
In article <rbisrael.20100627222655$02d7(a)news.acm.uiuc.edu>,
Robert Israel <israel(a)math.MyUniversitysInitials.ca> wrote:
>"rancid moth" <rancidmoth(a)yahoo.com> writes:
>
>> product(k=1..m) Binomial(2k,k)^(8*(2k+1)) = ?
>
>Well, if p is a prime, by a theorem of Kummer the highest power of p in
>binomial(2k,k) is the number of times you "carry 1" in adding k + k in
>base p.
>If you call that C(k,p), your answer is
>
>product_p p^(8 sum_{k=1}^m (2k+1) C(k,p))
>
>the product being over all primes <= 2m.

The number of base p carries in adding k+k is (2 S_p(k) - S_p(2k))/p
where S_p(k) is the sum of the base p digits of k.

Rob Johnson <rob(a)trash.whim.org>
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