failing to install sagemath on ubuntu 18.04 LTS

Question

Recently, I have install Ubuntu 64amd making duak boot with Windows 7 32bit. Everything is ok ,but I'm unable to install sagemath in it. it says " unable to locate the package sagemath-upstream-binary" even when the code is correct. may I know why?

Here are the complete code I have used:

sudo apt-add-repository -y ppa:aims/sagemath
sudo apt-get update
sudo apt-get install sagemath-upstream-binary  

Below are the terminal codes:

kutubuddin@kutubuddin-h81m-s:~$ sudo apt-add-repository -y ppa:aims/sagemath
[sudo] password for kutubuddin: 
Ign:1 http://ppa.launchpad.net/aims/sagemath/ubuntu bionic InRelease           
Get:2 http://security.ubuntu.com/ubuntu bionic-security InRelease [69.9 kB]    
Err:3 http://ppa.launchpad.net/aims/sagemath/ubuntu bionic Release             
  404  Not Found [IP: 91.189.xx.xx xx]
Hit:4 http://in.archive.ubuntu.com/ubuntu bionic InRelease                     
Hit:5 http://in.archive.ubuntu.com/ubuntu bionic-updates InRelease             
Hit:6 http://in.archive.ubuntu.com/ubuntu bionic-backports InRelease           
Reading package lists... Done                                  
E: The repository 'http://ppa.launchpad.net/aims/sagemath/ubuntu bionic Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
kutubuddin@kutubuddin-h81m-s:~$ sudo apt-get update
Ign:1 http://ppa.launchpad.net/aims/sagemath/ubuntu bionic InRelease
Get:2 http://security.ubuntu.com/ubuntu bionic-security InRelease [69.9 kB]
Hit:3 http://in.archive.ubuntu.com/ubuntu bionic InRelease                     
Err:4 http://ppa.launchpad.net/aims/sagemath/ubuntu bionic Release             
  404  Not Found [IP: 91.189.xx.xx.xx]
Get:5 http://in.archive.ubuntu.com/ubuntu bionic-updates InRelease [65.4 kB]   
Hit:6 http://in.archive.ubuntu.com/ubuntu bionic-backports InRelease           
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/aims/sagemath/ubuntu bionic Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
kutubuddin@kutubuddin-h81m-s:~$ sudo apt-get install sagemath-upstream-binary
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package sagemath-upstream-binary

Answer 1

The PPA you mentioned does not have packages for 18.04 LTS.

In case of Ubuntu 18.04 LTS Bionic Beaver you do not need any PPA to install SageMath.

You can simply remove the PPA (if added before):

sudo apt-add-repository -r ppa:aims/sagemath

and then install sagemath from repository:

sudo apt-get install sagemath