That's what I have in my time system UIT (linked earlier). I renamed the days to nullday, unday, duoday, triday, quadday, pentday, hexday, heptday, octday, nonday. One nice feature is that if I tell you that it's 1st Unday today, you can see immediately that it's the 12 day of the year (since 0th Nullday is the first day of the year).