BW
-----maxima-bounces at math.utexas.edu wrote: -----
>To: maxima at math.utexas.edu
>From: andre maute
>Sent by: maxima-bounces at math.utexas.edu
>Date: 09/17/2007 04:50AM
>Subject: finding subterms in a bigger term
>
>Hi Maxima mailinglist,
>
>I'm experimenting with non-classical orthogonal polynomials.
>
>I have set,
>
>gammalim : -2;
>
>because I don't want the gamma function to be evaluated.
>
>I have the constraints
>a > -1, a real, and b > -1, b real
>but they are not used within my Maxima source at the moment.
>
>I have terms being polynomial in gamma terms like the following
>
>--------------------------------------------------------------------------
>----
>(%o13) ((gamma (a + 1) gamma (b + 1) gamma (b + a + 3)
> 2 2
> + (- gamma (a + 1) gamma (b + 2) + 2 gamma(a + 1) gamma(a + 2) gamma(b +
>1)
> 2 2 2
> gamma(b + 2) - gamma (a + 2) gamma (b + 1)) gamma (b + a + 2))
> 2 2
> gamma (b + a + 4) + (gamma (a + 1) gamma(b + 1) gamma(b + 3)
> - 2 gamma(a + 1) gamma(a + 2) gamma(b + 1) gamma(b + 2)
> 2 2
> + gamma(a + 1) gamma(a + 3) gamma (b + 1)) gamma(b + a + 2) gamma (b + a
>+ 3)
> gamma(b + a + 4)) gamma(b + a + 5)
>--------------------------------------------------------------------------
>----
>
>Question:
>
>How can I find minimal n1, n2, n3 such that
>
>gamma(a+n1), gamma(b+n2) and gamma(a+b+n3)
>
>are appearing in the above term?
>
>I want to use gamma(x+1) = x*gamma(x)
Before you write your own code to do this, try using the functions
'makefact' and
'minfactorial.' For example
(%i12) gamma (a + 1) * gamma (b + 1) * gamma (b + a + 3) / (gamma(a) *
gamma(b) * gamma(a+b))$
(%i13) makefact(%)$
(%i14) minfactorial(%);
(%o14) a*b*(b+a)*(b+a+1)*(b+a+2)
If this doesn't work, there are other approaches.
BW