MathGroup Archive 2000

[Date Index] [Thread Index] [Author Index]

Search the Archive

'strange' simplification problems - why?

  • To: mathgroup at
  • Subject: [mg22973] 'strange' simplification problems - why?
  • From: lobozc at
  • Date: Sat, 8 Apr 2000 14:44:43 -0400 (EDT)
  • Sender: owner-wri-mathgroup at

> Product[lmb(M-i)/(mu(i+1)),{i,0,k-1}]


> ((-1)^k*lmb^k*(mu^(-1))^k Pochhammer[-M, k])/k!

there are two things wrong with that for me:

a)  lmb^k*(mu^(-1))^k  is just a longwinded way of saying (lmb/mu)^k -
and I get the long form also after FullSimplify. What am I doing wrong
here? how could I get that to the simpler form? [short of replacing it
by hand]

b) more difficult: the 'real' answer to the original problem is
(lmb/mu)^k Binomial[M, k]   - which is preferable as it avoids the
Gamma function. How can I coach Mathematica to deliver answers in Binomial
coefficients rather than in Gammas?

Sent via
Before you buy.

  • Prev by Date: Problems with InitializationCell
  • Next by Date: Re: uninstalling mathreader
  • Previous by thread: Problems with InitializationCell
  • Next by thread: Re: 'strange' simplification problems - why?