Re: Bug in SeriesCoefficient in 7.0
- To: mathgroup at smc.vnet.net
- Subject: [mg98050] Re: Bug in SeriesCoefficient in 7.0
- From: ADL <alberto.dilullo at tiscali.it>
- Date: Sun, 29 Mar 2009 02:42:46 -0500 (EST)
- References: <gqia68$okh$1@smc.vnet.net>
Given that the bug is there, a possible workaround in version 7 could
be to use FindSequenceFunction:
NC = 9; (* numeber of coefficients required *)
gf = FindSequenceFunction[
Table[
{n, SeriesCoefficient[Exp[-2*z]/(1 - z)^2, {z, 0, n}]},
{n, 0, NC}
],
n];
sgf = FullSimplify[gf, n \[Element] Integers]
====> (E^2*(-1)^n*2^(n + 2) + Gamma[n + 4, -2]) / (E^2*Gamma[n + 3])
If we call gf6 the coefficient form returned by Mathematica 6.01,
FullSimplify[gf6 - sgf] returns 0.
ADL