days-between-dates Solver equation for 17b

[Massimo Gnerucci]

(10-08-2018 09:44 AM)StephenG1CMZ Wrote:  I had been told that the reason December was called Dec although it was the 12th month now was because Julius added a month, and then Augustus copied him and added another month - not that it was because years used to start in March.
If both are true, December should be called October.

Nobody added a month: quintilis became iulius (July) and sextilis became augustus (August).
And maybe a day was added to augustus (taking it from february) to make it equal to iulius (uncertain).

Hereabout the year started in march, since then comes spring, and a new beginning.