I've just downloaded and installed Mathematica from the Wolfram web-site on my Raspberry Pi 4. When I launch it, I'm prompted to launch an activation key and/or password. I contacted Wolfram as where I might find said key/password and they've been singularly unhelpful :
"Please go to https://www.raspberrypi.org/ for help.
Wolfram does not provide assistance with Raspberry-Pi issues.
I hope this helps.
Customer Services Representative
Wolfram Research Europe Ltd"
Can any one help?