Re: Problem with RSolve
- To: mathgroup at smc.vnet.net
- Subject: [mg62689] Re: Problem with RSolve
- From: "Scout" <Scout at nodomain.com>
- Date: Wed, 30 Nov 2005 22:09:05 -0500 (EST)
- References: <dmk02k$781$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
"Jean Guillaume Pyraksos" <wissme at hotmail.com> ha scritto nel messaggio news:dmk02k$781$1 at smc.vnet.net... >I can't get this one solved, can you help ? > > RSolve[{c[n] == c[n - 1] + (n^2) Log[n], c[0] == 0}, c[n], n] > > I am interested in the principal part of c[n], which should be 1/2 n^2 > Log[n]^2 ?... > > Thanks, using Mathematica 4.1.0.0 > > JG > Hi, I've tried the recurrent equation on my system. I get these results: "4.0 for Microsoft Windows (April 21, 1999)": {} no solutions with Indeterminate expressions and PolyLog syntax error :-( Instead, "5.2 for Microsoft Windows (June 20, 2005)": In[]:= RSolve[{c[n] == c[n - 1] + (n^2) Log[n], c[0] == 0}, c[n], n] Out[]= \!\(\* RowBox[{"{", RowBox[{"{", RowBox[{\(c[n]\), "\[Rule]", RowBox[{\(1\/36\), " ", RowBox[{"(", RowBox[{\(\(-69\)\ n\), "-", \(57\ n\^2\), "-", \(14\ n\^3\), "+", \(36\ Log[Gamma[1 + n]]\), "+", \(72\ n\ Log[Gamma[1 + n]]\), "+", \(36\ n\^2\ Log[Gamma[1 + n]]\), "-", \(36\ Log[Gamma[2 + n]]\), "-", \(72\ n\ Log[Gamma[2 + n]]\), "-", \(36\ n\^2\ Log[Gamma[2 + n]]\), "-", RowBox[{"36", " ", RowBox[{ SuperscriptBox["Zeta", TagBox[\((1, 0)\), Derivative], MultilineFunction->None], "[", \(\(-2\), 2\), "]"}]}], "+", RowBox[{"36", " ", RowBox[{ SuperscriptBox["Zeta", TagBox[\((1, 0)\), Derivative], MultilineFunction->None], "[", \(\(-2\), 2 + n\), "]"}]}]}], ")"}]}]}], "}"}], "}"}]\) Regards, ~Scout~