[seqfan] Re: Chewing an old bone

[David Wilson]

 From a visual standpoint, your function would probably work just as 
well, although it turns
out that |qlog(x)| is closer to |log(x)| than is your proposed function 
for every nonzero x.

BTW, qlog is the inverse of f(x) = 10^x - 10^-x, which if you 
contemplate for a bit, explains
why it hugs log so closely for large values.

On 10/13/2011 5:36 AM, Alois Heinz wrote:
>
> The idea is good.
>
> But why not
>
>    signum(a(n)) * log(|a(n)|+1)
>
> which is compatible with log(|a(n)|+1) for nonnegative sequences?
>
> Alois
>
> Am 13.10.2011 04:14, schrieb David Wilson:
>>
>> My suggestion to improve this situation is as follows: For 
>> large-valued sequences, instead of plotting
>> log(a(n)+1) or log(|a(n)|+1), plot
>>
>>     qlog(n) = arcsinh(a(n)/2)/(ln 10)
>
>
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