What determines {default} location of :0, :1 & :2?

[Thomas Lübking]

On Sonntag, 7. Juli 2013 18:46:12 CEST, Felix Miata wrote:

> only care that the first session started, whether by KDM or not, 
> go on vt7; that the second, whether that be :0 or :1 or :2, go 
> on vt8, and that the third, whether :0 or :1 or :2, go on vt9. I 

Occupy vt1-6
https://wiki.archlinux.org/index.php/Systemd_FAQ#Q:_How_do_I_change_the_number_of_gettys_running_by_default.3F

Cheers,
Thomas