Karim Belabas on Wed, 03 Aug 2011 21:04:55 +0200


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Re: Bessel Functions


* Andreas Enge [2011-08-03 19:38]:
> Alternatively, you may modify the default series precision by
> \ps 500
> Then
> taylor(1/(1-x),x)
> or
> Ser(1/(1-x))
> yields the desired result, I assume this will work for older Gp versions
> as well.

The simplest solution is to avoid taylor altogether:

  1/(1-x) * (1 + O(x^500))

[ Exercise: why is "*(1+O(x^500))" in general different from the
simpler "+ O(x^500)" ? ]

Cheers,

    K.B.
--
Karim Belabas, IMB (UMR 5251)  Tel: (+33) (0)5 40 00 26 17
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