I hav the same (correct) result. No issue with Mojave so far.

Sorry for the typo. (fixed).

No clue what the expression should evaluate to. My only concern was getting some kind of reasonable output.

For what's worth, I get the same output with the Mathematica 12 beta, which has not been released. (I don't keep older versions around.)

Is Mathematica 11 compatible with Mac OS Mojave

I just tested your input on 11.3 under Mojave. Seems to work ok.

In[1]:= expansion=Series[Sin[Q r]/(Q r),{r,0,5}]

Out[1]= 1-(Q^2 r^2)/6+(Q^4 r^4)/120+O[r]^6

I've had no issues using 11.3 under Mojave, but (obviously) I have not tested all functionality.

Does anyone have information about whether Mathematica 10.0.2 works fine on Mojave?

I updated to Mojave on my MacBook Pro last week and this morning I got problems with Mathematica 11.3...

expansion = Series[Sin[Q r]/(Q r), {r, 0, 5}]

gave me a rubbish output with missing factors in the terms. (I tried to paste the output here but it is difficult to read).

Hello, Thanks for your reply. I've tried your suggestions, twice, but I still have the same problem. I'll contact Support. Thank you.

I've switched to Mojave and now the Front End doesn't open. The app runs in background but there is no way to use it (except from a Terminal).

I've reinstalled 11.3.0 on the Mac but the problem persists.

Does anybody have an idea about what the problem could be? Thanks.

An analysis on the process shows:

2018-10-01 17:13:55.066 sample[26384:827987] Failed to create CSSymbolicatorRef for pid 26375 Mathematica

Sampling process 26375 for 3 seconds with 1 millisecond of run time between samples

Sampling completed, processing symbols...

Analysis of sampling Mathematica (pid 26375) every 1 millisecond

Process: Mathematica [26375]

Path: /Applications/Mathematica.app/Contents/MacOS/Mathematica

Load Address: 0x1000

Identifier: com.wolfram.Mathematica

Version: ???

Code Type: X86

Parent Process: ??? [1]

Date/Time: 2018-10-01 17:13:55.011 +0100

Launch Time: 2018-10-01 17:13:49.876 +0100

OS Version: Mac OS X 10.14 (18A391)

Report Version: 7

Analysis Tool: /usr/bin/sample

Physical footprint: 8K

Physical footprint (peak): 8K

Call graph:

2677 Thread_827531: Main Thread   DispatchQueue_<multiple>

  2677 ???  (in <unknown binary>)  [0xcfc000]

Total number in stack (recursive counted multiple, when >=5):

Sort by top of stack, same collapsed (when >= 5):

    ???  (in <unknown binary>)  [0xcfc000]        2677

Binary images description not available

Sample analysis of process 26375 written to file /dev/stdout

Are there any known compatibility problems with earlier versions of Mathematica than 11.3, back to 10.0.2?

I am only interested in new compatibility problems specific to Mojave, not those that were also present in High Sierra (such as the one with the font chooser dialog).

Thanks for the update on the official support. The dialog that Mojave puts up when starting a 32 bit app can be a bit confusing, though. Mathematica is my only "critical" app that is not yet 64 bit, and if others are in the same boat, Mathematica maybe the only app where they see the dialog, though.

Mathematica 11.3 has a 32 bit Front end. Mojave runs 32 bit apps, but gives you a warning. The next macOS will not run 32 bit apps.

The next release of Mathematica will surely be 64 bit -- as shown in Stephen Wolfram's Twitch sessions -- so other than the warning (which appears just once, I believe), we are ok.