CAS bug when calculating sum(1/n,n,1,medium_value)

[Lukas]

I recently came across this video showing a CAS bug on the HP Prime. I think this bug hasn't been discussed here yet.

Basically it seems that sum(1/n,n,1,x) evaluates in CAS for low values of x (up until 2968 on my G2). For very large values, like 100000000000, it too works just fine.

However, for values starting from 2969 (on my G2; it might be a different value on the G1) the result of the calculation is undef+undef.

I haven't tested from what value x between 2969 and 100000000000 it starts to work again.

I think this is essentially a xcas/giac problem, since I run into a similar issue on my computer when I test it in giac:

Code:


1>> sum(1/n,n,1,5527)
Done
// Time 0.03

Note that on your computer you might actually get a result, just like giac on my computer can evaluate sum(1/n,n,1,2969) whereas my G2 cannot do it. I guess it depends on the speed of your computer at what value x is stops to work as it should.

It seems to be a CAS-only problem, since you can calculate sum(1/n,n,1,2969) just fine in Home.