[seqfan] Re: "Graph" button gives wrong results with large numbers

[Joerg Arndt]

Sounds like the good old IEEE-754 double's limits,
that are at exponents about +-307

If only logarithms are needed than a program
that reads the prefix (up to 15 decimal digits)
and uses the length L of the number
could, for plotting, return
log(number) = log(prefix) + log(L)/log(10)
(correct?).

Best regards,   jj


* Neil Sloane <njasloane at gmail.com> [Nov 20. 2017 17:05]:
> This came up recently in a discussion about drawing the graph of a sequence
> with very large numbers.  This is nothing new, we have always known about
> this bug, but it is worth reminding people:
> 
> There is a real problem with the "graph" button when the terms
> of the sequence are bigger than about 300 digits.
> 
> The trouble is that we use the statistics language R to make the plots,
> and R cannot handle very large integers.  If a number is greater than about
> 10^300,
> [...]