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 Author Comment/Response JD 07/08/13 6:42pm In Response To 'Re: Solving for when a summation reaches a value.'---------I tried it on my computer and the graph I came up with is a simple x=y graph. Maybe if the y side of the graph was the LCM (1,2,...n)and the x side of the graph was n, I could get a ballpark estimate. I looked into the reference you gave for Mathworld. I had been there long ago, but I did see that Psi(n)= ln(LCM(1,2,3,...,n) so if I understand logs correctly, then E^[Psi(n)]= (LCM(1,2,3,...,n) and then the following should give me the number of digits of the LCM In[]:= Solve[3 <= Ceiling[log[E^(\[Psi] (n))]] && n > 0, n ][[1]] During evaluation of In[]:= Solve::nsmet : "This system cannot be solved with the methods \ available to Solve. \!\(\*ButtonBox["\[RightSkeleton]", Appearance->{Automatic, None}, BaseStyle->"Link", ButtonData:>"paclet:ref/Solve", ButtonNote->"Solve::nsmet"]\)" Out[]= 3 <= Ceiling[log[E^(n \[Psi])]] && n > 0 Ceiling[log[E^(\[Psi] (9))]] During evaluation of In[38]:= Syntax::tsntxi : "\"\[NoBreak][Ceiling[log[\[ExponentialE]^(\[Psi] \ (9))]]]\[NoBreak]\" is incomplete; more input is needed.\[NoBreak]""\ \[NoBreak]" During evaluation of In[38]:= Syntax::sntxi : "Incomplete expression; more input is needed \ \[NoBreak]""\[NoBreak]." - Okay, so I'm giving the computer really simply stuff and it just gives it back to me with the last entry. Since I am so new to Mathematica, I assume that there has to be something completely basic that I am not doing. I can't even get it to Evaluate[ã^(y(9))] I am using a notebook, .nb file. I right click on the cell after I'm finished and use Evaluate Cell. Nothing is happening. I should have got an answer of e^2520 or some number. If this thing doesn't put out soon, I'm going to explode. URL: ,

 Subject (listing for 'Solving for when a summation reaches a value.') Author Date Posted Solving for when a summation reaches a value. JD 07/08/13 06:54am Re: Solving for when a summation reaches a value. Bill Simpson 07/08/13 4:36pm Re: Re: Solving for when a summation reaches a ... JD 07/08/13 6:42pm Re: Solving for when a summation reaches a value. Bill Simpson 07/09/13 01:15am
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