Octave dependency problem on Ubuntu 16.04

I'm trying to install octave on freshly installed Ubuntu 16.04. So I've tried these commands:

sudo apt-add-repository ppa:octave/stable
sudo apt-get update
sudo apt-get install octave

After 'sudo apt-get update', I got this errors and warnings:

Err:9 http://ppa.launchpad.net/octave/stable/ubuntu xenial/main amd64 Packages                                                      
  404  Not Found
Err:10 http://ppa.launchpad.net/octave/stable/ubuntu xenial/main i386 Packages                                                      
  404  Not Found

W: The repository 'http://ppa.launchpad.net/octave/stable/ubuntu xenial Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Failed to fetch http://ppa.launchpad.net/octave/stable/ubuntu/dists/xenial/main/binary-amd64/Packages  404  Not Found
E: Failed to fetch http://ppa.launchpad.net/octave/stable/ubuntu/dists/xenial/main/binary-i386/Packages  404  Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.

And after 'sudo apt-get install octave':

Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 octave : Depends: libarpack2 (>= 2.1) but it is not going to be installed
          Depends: libcholmod3.0.6 but it is not going to be installed
          Depends: liboctave3 (= 4.0.0-3ubuntu9) but it is not going to be installed
          Depends: libosmesa6 (>= 10.2~) but it is not going to be installed
          Recommends: libopenblas-base but it is not going to be installed or
                      libatlas3-base but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

After these, when I try 'sudo apt-get -f install':

Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

I've tried installing dependencies so that I can compile source code, and similar errors appeared (sudo apt-get install libarpack2):

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libarpack2 : Depends: libgfortran3 (>= 4.6) but it is not going to be installed
              Depends: liblapack3 but it is not going to be installed or
                       liblapack.so.3
E: Unable to correct problems, you have held broken packages.

What can I do now?

Solution 1:

16.04 is new and all packages are not ready to use in all servers. Using Main Server to download packages will solve your problem.

1. System Settings
2. Software & Updates
3. Select "Main Server" from "Download from" section