@acer @roman_pearce 

I contacted the Maple techical support. After a few mail back and forth I received (yesterday evening) the following bug confirmation and a promis that it is solved in Maple 2017.

After a few more experiments with Maple 2016.2, I can see that there is in fact a computational bug for expressions like this (i.e. where 100+ instances of multiple variables are mishandled in simplification).  Luckily, this issue appears to have been resolved in Maple 2017 (see attached worksheet), so we recommend upgrading to that version when it is released.

- Jonas

@vv Thanks, it is nice with a workaround. I got the following from Maple technical support:

After a few more experiments with Maple 2016.2, I can see that there is in fact a computational bug for expressions like this (i.e. where 100+ instances of multiple variables are mishandled in simplification).  Luckily, this issue appears to have been resolved in Maple 2017 (see attached worksheet), so we recommend upgrading to that version when it is released.

@Preben Alsholm @gkokovidis 

I have now tried The suggested methods in Maple 2016.1. It gives different results every now and then, when I open a new sheet and copy-and-paste the expand expression. I have also tried replacing the variables with numbers in a text editor, and all programs that I have tried gives the same result as Maple 17 GUI/Mathematica/Python 2.7.12/ Sympy 1.?/MATLAB 2016a. Thus, I still belive in the result:

-2*a^23*h^40*o*v^2+2*a^23*h^40*v^3

I susspect that there is some kind of bug here, simply given the different results across Maple versions.

Here is my Maple file: https://www.dropbox.com/s/afxf5yl3a5y10gk/trust_issues.mw?dl=0

Best regards, Jonas