https://community.home-assistant.io/t/add-easier-solution-for-loops-in-automations-scripts/108508/45
As Argument (or just hard code #):
cat << 'EOF' >volup.yaml
volup:
sequence:
repeat:
count: '{{ count }}'
sequence:
- service: media_player.volume_up
entity_id: media_player.freesoftwareservers
EOF