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06/07/13 4:59pm

In Response To 'Re: Re: bug in Series[] function'
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The problem seems to be in Sum. The result for the infinite summation appears wrong.

In[46]:=
oneK = Sum[z^g[n]*4*3^(n - 1), {n, 1, 1000}];

In[47]:=
inf = Sum[z^g[n]*4*3^(n - 1), {n, 1, Infinity}]

Out[47]= -((4 z)/(-1 + 3 z))


In[48]:= Plot[{oneK, inf, oneK - inf} , {z, 0, 0.3},
PlotStyle -> {Red, Blue, {Thick, Green}}]

(lines diverge)

In[49]:= {oneK, inf, oneK - inf} /. z -> 0.1000000000000000000000000000000000000

Out[49]= {0.412472253350726926799440547948014405,

0.571428571428571428571428571428571429,

-0.15895631807784450177198802348055702}

I will report the error to developers.

URL: ,

Subject (listing for 'bug in Series[] function')
Author Date Posted
bug in Series[] function Eric Freden 06/03/13 2:31pm
Re: bug in Series[] function yehuda 06/06/13 09:50am
Re: Re: bug in Series[] function Eric Freden 06/06/13 11:44am
Re: Re: Re: bug in Series[] function Forum Modera... 06/07/13 4:59pm
Re: Re: Re: Re: bug in Series[] function Forum Modera... 06/10/13 2:11pm
Re: Re: Re: bug in Series[] function yehuda 06/08/13 2:22pm
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